Peterkin v Tadros [2026] NSWSC 1185 | Case summary | Zoe

NSWNSWSC

Peterkin v Tadros

[2026] NSWSC 1185

Supreme Court of NSW|2026-09-29|Before: Sirtes J

View on NSW Caselaw

At a glance

Source facts

Court

Supreme Court of NSW

Decision date

2026-09-29

Before

Sirtes J

Catchwords

TORTS – negligence – medical negligence – general practitioner – where patient presenting with rectal symptoms – where defendant failed to take history of duration of symptoms – where defendant failure to refer for specialist investigation – breach of duty established TORTS – negligence – causation – where delayed diagnosis of rectal cancer – counterfactual date of diagnosis – where cancer recurred – life expectancy – factual causation and scope of liability established TORTS – negligence – contributory negligence – where plaintiff failed to seek further medical attention – apportionment reserved

Source

Original judgment source is linked above.

Catchwords

TORTS – negligence – medical negligence – general practitioner – where patient presenting with rectal symptoms – where defendant failed to take history of duration of symptoms – where defendant failure to refer for specialist investigation – breach of duty established TORTS – negligence – causation – where delayed diagnosis of rectal cancer – counterfactual date of diagnosis – where cancer recurred – life expectancy – factual causation and scope of liability established TORTS – negligence – contributory negligence – where plaintiff failed to seek further medical attention – apportionment reserved

Judgment

Source: NSW Caselaw (www.caselaw.nsw.gov.au). Converted to plain text by ZoeLaw. Not the official version.

Medium Neutral Citation: Peterkin v Tadros [2026] NSWSC 1185

Hearing dates: 7–10 September 2026

Date of orders: 29 September 2026

Decision date: 29 September 2026

Jurisdiction: Common Law

Before: Sirtes J

Decision: (1) The Defendant is liable to the Plaintiff in negligence, and the Plaintiff was contributorily negligent.
(2) The parties are to send to my chambers, by 13 October 2026, competing submissions on damages, apportionment and costs. Such submissions are to be no more than 10 pages, in size 12 font, with 1.5 spacing between each line and with margins of no less than 2.54 cm on all sides of the page. (3) Should the parties consider it necessary, they are to contact my chambers by 5pm on 3 October 2026 for the purpose of having the matter listed for hearing on damages. (3) Costs are reserved.

The Plaintiff commenced these proceedings on 21 May 2026. The Plaintiff alleges that he presented at the August 2022 Consultation complaining of painful defecation, a sense of urgently needing to open his bowels, as well as rectal bleeding. Those symptoms were said to have affected him for one day. The Defendant’s clinical notes from the August 2022 Consultation recorded a medical history of haemorrhoids. The Defendant says he visually examined the Plaintiff’s anus. He did not perform a digital examination.
The Statement of Claim notes that the Plaintiff’s prognosis is uncertain and he has a “limited life expectancy”. This is addressed further below.
The central allegation against the Defendant is that a reasonable and competent person in his position would have taken precautions to minimise the risk of harm materialising pursuant to s 5B(2) of the Civil Liability Act 2002 (NSW) (the CLA). There are 18 bullet points under the heading “Particulars of Precautions” alleged against the Defendant as well as a further 18 “Particulars of Negligence”.
The Plaintiff filed an Amended Statement of Claim on 3 September 2026. Only two paragraphs were amended.
The first amended paragraph corrected the date of the Plaintiff’s consultation with the Defendant and added that the Plaintiff denies reporting (or having) any history of haemorrhoids.
The second amended paragraph added that Dr Etemad (the Plaintiff’s usual general practitioner) did not perform a physical examination of the Plaintiff’s anus or rectal region on 8 October 2023. It also noted Dr Etemad’s referral letter to Dr Hamilton (a colorectal specialist) “for an opinion and management of rectal bleeding ([haemorrhoid]?)” [sic].
The Defendant relies upon ss 5B, 5C, 5D and 5O of the CLA. Should negligence be found, he relies upon s 5R. I will deal with each of these as they arise.
The meaning of “negligence” is contained in s 5 of the CLA, being “failure to exercise reasonable care and skill”.
The alleged breach of duty is based on the pre-conclave reports of Dr Chambers. As to causation, the Plaintiff relies on the evidence of Associate Professor Pendlebury, oncologist, whose report contains certain factual assumptions. The Defendant claims that those assumptions are erroneous and that, once they are removed, the Plaintiff is unable to establish breach of duty or causation.

The Plaintiff is a 43-year-old man who lives with his wife, Mrs Kristy-Lee Peterkin, and their five-year-old daughter. They intended to have a second child, though those plans have been affected by the Plaintiff’s illness.
The Plaintiff worked for approximately 15 years as a personal trainer. He has been on unpaid leave since November 2025. Mrs Peterkin says that, before his illness, the Plaintiff was energetic and heavily involved in every aspect of their family life.
The August 2022 Consultation occurred on 23 August 2022, when the Plaintiff attended the Defendant’s medical practice in Gledswood Hills. The Defendant was not the Plaintiff’s usual GP. At the appointment, the Plaintiff complained that it was painful to defecate and that, after defecating, he would experience minimal bright rectal bleeding.
The Defendant, after allegedly inspecting the Plaintiff’s anus visually, diagnosed him with haemorrhoids. The Defendant prescribed a suppository and supplied the Plaintiff with an educational pamphlet concerning haemorrhoid symptoms and treatment.
On 8 October 2023, the Plaintiff attended the same medical practice and saw his usual GP, Dr Samira Etemad. Dr Etemad’s notes from this appointment record that the Plaintiff complained of rectal bleeding several times a week, though there was no pain when defecating. Dr Etemad, who observed that the Plaintiff had a “small haemorrhoid”, referred him to Dr Aurelius E Ricardo Hamilton “for an opinion and management of rectal bleeding ([haemorrhoid]?)”.
The Plaintiff did not see Dr Hamilton before his next consultation with Dr Etemad on 22 February 2024, when he again complained of rectal bleeding. At that appointment, Dr Etemad advised the Plaintiff to see Dr Hamilton as soon as possible. She advised him that a colonoscopy was needed to determine whether the Plaintiff’s issues were being caused by polyps, cancer or haemorrhoids. She provided the Plaintiff with another referral to Dr Hamilton. That referral was printed again on 7 March 2024, seemingly at the Plaintiff’s request.
On 8 May 2024, the Plaintiff again saw Dr Etemad. His presentation was largely unchanged from 22 February 2024. He had already attended a consultation with Dr Hamilton on 7 March.
On 15 May 2024, the Plaintiff attended Dr Hamilton at Campbelltown Hospital for the purpose of having a colonoscopy. Dr Hamilton’s digital examination of the Plaintiff found a hard rectal mass. The colonoscopy found that the 6 cm mass had broken through the Plaintiff’s rectal mucosa.
An MRI taken five days later revealed that the Plaintiff had a “mid to high rectal tumour” which had grown into the surrounding tissue. There were two likely regional metastases.
On 28 May 2024, the Plaintiff was diagnosed with mid-rectal adenocarcinoma. He was to undergo an intensive chemotherapy regimen followed by long-course radiotherapy and further chemotherapy.
The tumour’s size and location necessitated a defunctioning colostomy. The surgery was delayed until after the Plaintiff completed neoadjuvant therapy, which covers a range of preoperative therapies designed to shrink a tumour before surgery.
By 9 October 2024, the Plaintiff had completed his initial chemotherapy.
On 20 February 2025, the Plaintiff underwent a surgical resection (with a diverting ileostomy). A histopathology report revealed that, despite the neoadjuvant therapy, a “large amount of residual malignancy” remained. The cancer had metastasised to four lymph nodes. He recommenced chemotherapy.
The Plaintiff attended review appointments with Dr Hamilton on 7 July and 15 October 2025. At the latter appointment, Dr Hamilton noted that a recent CT scan indicated that the cancer may have metastasised to two lymph nodes.
On 5 November 2025, the Plaintiff underwent surgery to reverse his ileostomy. By that time, the cancer had spread to blood vessels and lymphatic channels near the tumour.
On 27 December 2025, the Plaintiff underwent surgery for a permanent colostomy and the insertion of a stent in his left ureter, which had become obstructed by lymph nodes swollen by the cancer’s invasion.

The Plaintiff’s lay evidence comprised his affidavit sworn 25 June 2026 together with an exhibit, being a thread of Facebook Messenger messages between the Plaintiff and Mrs Peterkin on 23 August 2022, plus the Plaintiff’s oral evidence taken on commission on Wednesday 1 July 2026 (the EOC). Mr Campbell of Counsel appeared for the Plaintiff in that examination and Mr Hutchings of Counsel appeared for the Defendant. Both also represented their respective clients at the hearing.
The Plaintiff also read the lay evidence of Mrs Peterkin, dated 25 June 2026, and a statement of Dr Samira Etemad, dated 4 September 2026.
The Defendant’s lay evidence comprised his own statement, dated 30 July 2026, to which his curriculum vitae was annexed.
The Plaintiff relied upon the following liability and causation expert evidence:
a report of Dr Dianne Chambers, general practitioner, dated 22 August 2025;
a report of Associate Professor Susan Pendlebury, radiation oncologist, dated 19 February 2026;
a supplementary report of Associate Professor Pendlebury, dated 24 July 2026;
a supplementary report of Dr Chambers, dated 29 July 2026;
a report of Dr Siddharth Sethi, gastroenterologist, dated 30 August 2026; and
a further supplementary report of Associate Professor Pendlebury, dated 4 September 2026.
The Defendant relied upon the following liability and causation expert evidence:
a report of Professor David Garne, general practitioner, dated 1 July 2026;
a report of Professor Stephen Clarke OAM, oncologist, dated 3 July 2026; and
a report of Associate Professor Vincent Ho, gastroenterologist, dated 27 August 2026.
The Plaintiff provided the following expert quantum evidence:
a report of Professor Richard Fox, oncologist, dated 22 April 2026;
a report of Dr Leon Turnbull, psychiatrist, dated 12 March 2026; and
a report of Keshika Naidoo, occupational therapist, dated 15 May 2026.
The Defendant provided the following expert quantum evidence:
a report of Victoria Gracey, occupational therapist, dated 9 July 2026.
The oncologists, Associate Professor Pendlebury and Professor Clarke, provided a joint report, dated 12 August 2026, arising from their expert conclave. The expert general practitioners, Dr Chambers and Professor Garne, also participated in an expert conclave and produced a joint report dated 13 August 2026. Because of the bifurcation of liability and quantum, no quantum evidence was read before me.

The Plaintiff later said that he did not associate having a colonoscopy with cancer.
Since September 2021, the Plaintiff had almost constantly felt an urgent need to go to the toilet for a bowel movement. This sense of urgency is termed “tenesmus”. The Plaintiff regarded it as a lingering effect of COVID-19, which caused issues with his bowels when he contracted it in September 2021. However, at that time, the urgency was not accompanied by pain. By August 2022, the Plaintiff made sure he was aware of the nearest toilet whenever he went out in public.
The Plaintiff ultimately conceded that he had been suffering for “maybe 5 to six months” from intermittent blood on toilet paper after defecating. When asked whether he could have been suffering the symptoms for perhaps a year, he did not exclude the possibility, saying “it’s entirely possible, but I don’t recall anything like that”. His wife had asked him about the blood several times prior to 23 August 2022. This is consistent with the message she sent to her husband before making the appointment.
The third theme concerned the acute nature of the Plaintiff’s presentation at the August 2022 Consultation. The Plaintiff claimed that he presented at the consultation with all of the symptoms set out at [46] above. However, he accepted that, before that date, he had regarded his symptoms as “a niggling problem” that “wasn’t very severe at all”. His evidence in cross-examination was that, before 23 August 2022, the feeling of urgency was not accompanied by pain. He said that until the day of the August 2022 Consultation, his urgency was not painful, and about two-thirds of his bowel movements were not painful either. The blood that accompanied his defecation was “pinkish in colour… just traces… it was never dark red”.
He maintained that he told the Defendant he felt very bloated, which he put down to constipation.
The following exchange occurred during cross-examination of the Plaintiff:

There was considerable disparity between the matters asserted by the Defendant in his statement or in his oral evidence (or both) and the content of the clinical note. The note did not contain a number of matters that the Defendant nevertheless maintained were discussed and communicated during the consultation. A summary of those is as follows:
the Defendant says that he made a positive finding of a haemorrhoid resembling a bulging dilated vein close to the anal verge. This was not in the clinical note. There is no reference to a “visualised prolapsing haemorrhoid” as pleaded at par 28(a)(ii) of the Defence;
the Defendant stated that he recommended a digital rectal examination, which was refused. The clinical note records that the Plaintiff was offered a chaperone and consented to an anal examination, but not the offer of a digital rectal examination or its refusal. The Defendant conceded that this (i.e. a refusal) would “usually” be recorded;
the Defendant stated that the Plaintiff told him that he felt a “lump” coming out on defecation, which shrank (or disappeared) afterwards. This was absent from the Defendant’s statement and the clinical note;
the Defendant stated that he asked whether the Plaintiff had any family history of bowel cancer, and that the Plaintiff answered that he had none. This is not recorded anywhere in the clinical note. This is relevant to the second pillar of the s 5O opinion at par 28(a)(ii) of the Defence;
the Defendant said that he asked the Plaintiff how long the bleeding had been present and was told one day. In the clinical note, however, the descriptor “1/7” attaches to the haemorrhoid. The Defendant accepted, during cross-examination, that the question of how long the bleeding had been occurring was fundamental;
the Defendant stated that he had asked the Plaintiff about the date of his previous haemorrhoids, but the Plaintiff was uncertain about the time. This is not recorded in the clinical note;
the Defendant’s statement records the Plaintiff telling him that he had the urge to defecate but could not. Nothing about urgency is recorded in the clinical note;
the Defendant said that the Plaintiff described his stool as harder than usual. This is not recorded in the clinical note;
the clinical note does not record the emergency department advice pleaded at par 28(a)(vii) of the Defence. It records “warning signs given with actions if it happens”;
during cross-examination, the Defendant identified polyps, inflammatory bowel disease and colorectal cancer as differential diagnoses where there is a longer history of the Plaintiff’s symptoms. The clinical note records only haemorrhoids, and then as a formal, rather than provisional, diagnosis; and
the Defendant stated that he drew a diagram of the position of the haemorrhoid on the education sheet. No copy of any annotated sheet appears in the material.

When asked whether he had asked the Plaintiff how long he had been affected by constipation, the Defendant said “[the Plaintiff] told me one day… if he had told me something different, I would have been putting that on- in the notes.” When asked whether the position of the haemorrhoid was recorded anywhere else in the practice records, the Defendant responded, “everything that happened on the consultation” is in the note. However, the Defendant accepted that, whilst the position of a haemorrhoid is “regularly” recorded, that information does not appear in the clinical note.
If the Defendant is correct that “everything that happened” is in the clinical note, it logically must follow that nothing of significance said during the appointment was absent from his notes. However, there were matters contained in his witness statement that were not included in those clinical notes and appeared after several years and many thousands of intervening consultations.
That is not in itself cause for criticism. The Defendant was, and remains, a busy GP. He estimated that he would have had 10,000 or more consultations between the single consultation he had with the Plaintiff on 23 August 2022 and the date he prepared his statement. One reason clinical notes are taken is so that vital patient information is recorded and not forgotten, which it otherwise would be owing to the high-volume nature of a family general practice.
The clinical note is almost entirely in the negative. It records few positive findings. Either the note is an incomplete record of a positive finding, or there was no positive finding to record and the diagnosis of haemorrhoids was made from the history the Defendant believed he had been given.
For those reasons, where there is disconformity between the clinical note and the Defendant’s own statement or oral evidence, I will prefer the clinical note. I will only accept the Defendant’s witness statement or oral testimony where it is consistent with the clinical notes.
There was nothing unusually memorable about this consultation. The Defendant’s claim to recall this consultation, so many years later, with so many intervening consultations, stretches credulity. The consultation was for a haemorrhoid, which the expert evidence established is a common complaint. I found the Defendant’s dogmatic rejection of the proposition that he was engaging in reconstruction to be hollow. That is not to say that he set out to mislead the Court. His reconstruction was from his usual practice, not a deliberately invented story.

None of Dr Etemad’s consultations with the Plaintiff before the August 2022 Consultation concerned the symptoms with which the Plaintiff presented to the Defendant.
The Plaintiff’s 8 October 2023 consultation with Dr Etemad was pivotal. The Plaintiff attended for the purpose of obtaining another script for haemorrhoid cream. During that consultation, the following occurred:
Dr Etemad asked the Plaintiff who had prescribed the medication and whether he had seen a specialist;
before writing the script, Dr Etemad went back through the clinical records, including those of the 23 August 2022 consultation;
Dr Etemad took a full history. The Plaintiff reported to her that he had experienced 5–10 ccs of rectal bleeding a few times a week for around 12 months;
Dr Etemad recorded several negatives: no pain on defecation, blood on toilet paper only (i.e. not mixed with stool), no diarrhoea, no abdominal pain, no constipation, no family history of bowel cancer or inflammatory bowel disease, no weight loss, no night sweats;
Dr Etemad offered a differential diagnosis of internal haemorrhoid, polyp, inflammatory bowel disease and cancer; and
Dr Etemad referred the Plaintiff to Dr Hamilton.
Dr Etemad had reason to doubt the haemorrhoid diagnosis. The Plaintiff reported that no haemorrhoid was visible or otherwise apparent to him. However, a haemorrhoid that bled at such a high rate over such a long time should have been visible to the Plaintiff. That, together with the 12-month history of bleeding, led her to conclude that the Plaintiff should be reviewed by a specialist. Although Dr Etemad provided the Plaintiff with the haemorrhoid script he sought, it was for symptomatic relief only. She continued to prescribe the medication even after the Plaintiff was diagnosed with cancer.
In her oral evidence, Dr Etemad stated that, at the 8 October 2023 consultation, cancer was “the least likely diagnosis” given the Plaintiff’s age, family history and absence of alarming features. She added that this accorded with the relevant guidelines. However, Dr Etemad added that cancer “was definitely in the back of [her] mind” and was part of her reason for referring the Plaintiff to Dr Hamilton.

As at 22 February 2024, the Plaintiff was still bleeding and had not made his appointment with Dr Hamilton. He had developed a new symptom, the sensation of pressure in his anal area. Dr Etemad’s evidence was that this new symptom made her consider cancer as likely, or at least one of the more probable diagnoses. She advised the Plaintiff to book with Dr Hamilton “ASAP” because a colonoscopy would be needed to determine the cause of the Plaintiff’s symptoms. She also encouraged the Plaintiff to contact her if he had trouble obtaining an appointment. She performed no rectal examination of any kind and made no diagnosis.
I pause to note that the Plaintiff contends that the Defendant ought to have referred him for a colonoscopy. During cross-examination, Dr Etemad confirmed that a GP cannot directly refer a patient for colonoscopy. Instead, a GP refers a patient to, relevantly, a colorectal surgeon or gastroenterologist who then completes the colonoscopy.
Dr Etemad chose Dr Hamilton because he had recently set himself up in the area and was likely to be available without an extended waiting period. The fact that Dr Hamilton worked in the public health system was also significant, as the Plaintiff was without private health insurance. Any colonoscopy would be booked with Campbelltown Hospital. Dr Etemad expected an appointment with Dr Hamilton would occur within two to four weeks of the October 2023 referral. She was certain that, unless Dr Hamilton was on leave, he would have been available for an appointment with the Plaintiff during that period.
The delay between an appointment with a specialist and a colonoscopy depends on how serious the specialist considers the patient’s presentation to be. The delay can be as short as a month, or, at Campbelltown Hospital, as long as 12 months. Dr Etemad recalled that Dr Hamilton considered the Plaintiff’s presentation to be serious. The estimated wait time was one month.
Dr Etemad gave evidence via audio-visual link. I found her to be a scrupulously honest witness who was attentive to the questions put to her. Dr Etemad did her best to assist the Court.
When presented with the Plaintiff’s history in October 2023, she did not accept the haemorrhoid diagnosis at face value. Although she did have an additional 12 months of reported history which was not available to the Defendant, her approach to the Plaintiff is a real-world benchmark.

The Plaintiff’s expert GP was Dr Dianne Chambers. The Defendant’s was Professor Garne. Both provided separate reports and later produced a joint report after attending a conclave. They gave concurrent evidence at the hearing.
While I have considered their individual and joint reports, I found their oral evidence most enlightening. Although it sharpened their areas of disagreement, it showed their areas of agreement to an even greater extent.
The GP experts did not, in substance, disagree about the standard of care. Their differences stemmed from the assumptions they were each asked to make. The contest between these experts therefore turns on questions of fact.
Dr Chambers’ opinion was that the Plaintiff’s symptoms could not plausibly have arisen in a single day. Nor, in her opinion, could they be explained by haemorrhoids. Dr Chambers concluded that a reasonable practitioner would have probed the Plaintiff for further information.
Dr Chambers’ evidence is that she would have asked detailed and open-ended questions, including “how long has this gone on?”, “have you had anything like this before?”, and additional questions regarding the duration of the urgency. Upon receiving that information, the Plaintiff should have been referred to a specialist.
Professor Garne’s opinion was that the Defendant acted reasonably based on the history provided by the Plaintiff. Professor Garne accepted that the Plaintiff’s symptoms called for inquiry as to their duration, that the urgency the Plaintiff described was tenesmus (which is not a feature of uncomplicated haemorrhoids), and that taking a longer history would have altered his approach.
Professor Garne said that he would have asked about the duration of the bleeding, the quantity and colour of the blood as well as the site, nature, severity and modifiers of the pain. He described these as “standard questions”. He agreed that the urgency feature alone would require further inquiry into how long it had been present and that history-taking is a dialogue in which the medical practitioner explores what he is told.
None of these matters were recorded in the Defendant’s clinical note. Professor Garne’s answer to that absence was that they may not have been recorded, but, nevertheless, “I’m assuming [the Defendant] would have asked”. The basis for that assumption is unclear. In any event, I have already found that the Defendant did not ask further questions.
The following propositions were accepted by both GP experts:
if a haemorrhoid had been seen by the Defendant, it should have been recorded;
the account given by the Plaintiff called for further inquiry from the Defendant, including as to duration;
urgency of the kind described by the Plaintiff is tenesmus, which is not a feature of uncomplicated haemorrhoids;
patients often self-diagnose. A doctor taking a history should look beyond any self-diagnosis; and
a 39-year-old man was generally low-risk in 2022 and rectal bleeding can be caused by many things other than cancer.

The experts were divided as to whether the Defendant actually saw a haemorrhoid. Professor Garne stated that the Plaintiff had an obvious external haemorrhoid which was at least grade 3. Because of that external haemorrhoid and the reported one-day duration of the symptoms, Professor Garne did not consider that a referral to a specialist was required on the day of the consultation.
My findings preclude Professor Garne’s opinion that everything was pointing towards the Plaintiff suffering a grade 3 haemorrhoid. Professor Garne twice acknowledged that the finding was not in the notes. He concluded that the Defendant should have recorded such an observation but did not. In this regard, I prefer Dr Chambers’ inferential argument: a note which meticulously records itemised negatives on inspection cannot sensibly be read as having omitted a single positive finding of a grade 3 haemorrhoid.
It should further be noted that:
Dr Hamilton advised the Plaintiff there was no evidence of haemorrhoids at the colonoscopy and both Professor Garne and Dr Chambers considered it unlikely that a grade 3 haemorrhoid would disappear within 18 months;
Dr Sethi considered that such a haemorrhoid was probably never there to begin with and was misdiagnosed; and
Associate Professor Ho and Dr Sethi agreed that haemorrhoids alone would not explain faecal urgency and Dr Chambers endorsed this position during the hearing.
The expert GP evidence provides further support for my earlier finding that the Defendant did not see a haemorrhoid. While the colonoscopy found that the Plaintiff had cancer, the results were “otherwise normal”. When asked whether it was likely that a prolapsed grade 3 haemorrhoid could effectively disappear within 18 months, Professor Garne said “[n]ot necessarily” if the Plaintiff stopped doing physical activity. However, the Plaintiff continued to both work as a personal trainer and play OzTag up until he was diagnosed with cancer. There is no suggestion in the evidence that he ceased physical activity.
Professor Garne’s own statement that patients under 40 presenting with rectal bleeding warrant referral for further investigation where there is a family history or the presence of other symptoms is consistent with my findings. Professor Garne accepted that urgency is one such “other symptom”. Based upon Professor Garne’s criteria, and without recourse to Dr Chambers’ material at all, referral for investigation was indicated notwithstanding the Plaintiff’s age.
The consequence of my finding that the Defendant did not see a haemorrhoid is that the two opinions of the GP experts effectively converge. This was confirmed by Professor Garne, who stated, “I agree with Dr Chambers if we assume the assumptions that she has been given”. I prefer the evidence and conclusions of Dr Chambers to those of Professor Garne principally because I am satisfied that the assumptions made by Dr Chambers, which informs her view that the Defendant conducted himself below the appropriate standard of care, are made out.

Dr Chambers evidence satisfies me that the Defendant was negligent at the August 2022 Consultation. Not only do I prefer Dr Chambers’ evidence, I observe the following:
the Defendant conceded that an enquiry as to how long a patient had been experiencing rectal bleeding was a fundamental question to ask. I find no evidence to support a finding that this was asked. I find that it was not asked;
the Defendant also accepted that bloating and constipation, taken together with bleeding and an urge to defecate, would be of concern (noting the contradictory nature of constipation versus tenesmus);
there is nothing to indicate that anything other than a haemorrhoid was discussed at the August 2022 Consultation. The other concerning symptoms were either ignored even though they had no connection with the presentation of a haemorrhoid;
both expert GPs agreed that the account given by the Plaintiff called for further enquiry from the Defendant; and
urgency is not a feature of haemorrhoids.
For those reasons, I find that the Defendant failed to take the particulars set forth at [168]–[169] above.
I find that the risk of harm was that a serious cause of the Plaintiff’s symptoms, including colorectal cancer, would not be diagnosed and that the delay in diagnosis would delay treatment.
That risk was foreseeable. The Defendant knew, or ought to have known of the risk. His concessions at [93] above and the pamphlet he handed the Plaintiff show as much.
The risk of harm to the Plaintiff in failing properly to probe the Plaintiff’s symptoms and, thereafter, to refer him for specialist consultation, was foreseeable, not insignificant, and was a precaution that the Defendant should have taken. Although the oncology experts agreed that cancer is found only in around 10% of patients investigated for rectal bleeding (and the Plaintiff was 39), rectal bleeding along with tenesmus required investigation.
As to s 5B(2) of the CLA, I find that the probability of harm, while low, was real and grave. The burden of precautions was slight, as the Defendant need only have asked additional questions and, upon receiving the answers, written a referral letter. The matters in s 5C of the CLA do not affect my conclusions.
In arriving at this conclusion, I have not merely accepted the evidence of Dr Chambers, but also the propositions accepted by the GP experts at [138] above.

The Plaintiff tendered several articles to which Associate Professor Pendlebury had referred in her reports. Those articles were not discussed at great length, indeed there was minimal discussion of them at all , nor were submissions devoted to them. Having considered each of the articles in question, I note that they do not address the same legal issues. Some go to breach, others causation. Moreover, they do not share similar subject matter. One article, “Rate of growth of untreated colorectal tumours” (2020) 4 (6) BJS 1200 is directed towards the consequences of delay in diagnosis. Another, “Diagnostic Yield of Colonoscopy by Presenting Symptom” (2008) 43 Scandinavian Journal of Gastroenterology 356 concerns the presentation of symptoms and the circumstances in which a colonoscopy would be undertaken. Some of them are derived from small sample sizes, while others are not current owing to rapid developments in treatment over the last five years.
The articles are of little assistance. I have instead placed greater weight on the opinions expressed by Professor Clarke and Associate Professor Pendlebury in their reports and oral evidence.
Professor Clarke considered the Plaintiff’s cancer to be slow growing and that it was stage 3 at all possible times, even at the time of the August 2022 Consultation. The Plaintiff submits that Professor Clarke provided no published growth rates to counter the publications upon which Associate Professor Pendlebury relied. When asked, during cross-examination, about the absence of cited literature concerning his opinions, Professor Clarke referred to an article “in [his] bag”, which article was produced. The Plaintiff submitted that the article in question is confined to a study of advanced mucinous colorectal cancers. The Plaintiff, who submits that he did not have such a cancer as at the August 2022 Consultation, argues that the article is largely irrelevant. The Plaintiff concedes that the article may be relevant in so far as it relates to the Plaintiff’s life expectancy. However, he maintains that it is irrelevant with respect to the expected growth rate of the Plaintiff’s cancer. This article is discussed further below.

In his report, Professor Clarke raised a question concerning Associate Professor Pendlebury’s qualifications to give evidence about the cancer from which the Plaintiff suffers. Professor Clarke expressed surprise that Associate Professor Pendlebury offered opinions on what he described as a highly specialised area outside of their expertise. He questioned whether they had attended a colorectal multidisciplinary team or managed a patient with a mucinous rectal tumour. He characterised Associate Professor Pendlebury as a breast cancer specialist and said that her comments were, of necessity, based on generic published information not supplemented by their own clinical experience. I note that Professor Clarke did not repeat that criticism during his oral evidence, nor was he asked, during cross-examination, whether he maintained it.
Associate Professor Pendlebury is a radiation oncologist who received her first consultant appointment in 1992. She spent approximately 10 years as a junior staff specialist at Royal Prince Alfred Hospital and had an academic association with the University of Sydney. Since 2005, she has been director of the Radiation Oncology Department at St Vincent’s Hospital, Sydney and has an academic association with the University of New South Wales. For the past 10 years, she has been the Director of Radiation Oncology for the Tamworth Section of Hunter New England Health.
Associate Professor Pendlebury described her Tamworth practice as a large general oncology practice. She is effectively the sole practitioner covering a vast region which extends from the town of Scone in the Upper Hunter region to the Queensland border. Some of her patients come from Armidale, others from southern Queensland. At any given time, Associate Professor Pendlebury is treating two or three colorectal cancers. She treats over 100 cases of such cancers annually and has been published in Surgical Clinics of North America on anal cancer.
During the hearing, Associate Professor Pendlebury gave evidence that she runs a multidisciplinary team which liaises with the Royal Prince Alfred Hospital for complex cases. She has been an active member of colorectal multidisciplinary teams since 2005.
To my mind, Associate Professor Pendlebury’s evidence that she treats over 100 cases of colorectal cancer annually is determinative. In that light, I consider Professor Clarke’s criticisms to be unjustified and, further, that Associate Professor Pendlebury eloquently answered Professor Clarke’s attack on her qualifications.

In Associate Professor Pendlebury’s opinion, the cancer would have been T2N0M0 stage 1 (i.e. present and invasive but not locally advanced) as at the time of the August 2022 Consultation. Professor Clarke’s opinion is that the cancer was locally advanced (i.e. stage 3) at all possible time points, including August 2022.
If Associate Professor Pendlebury is correct that the cancer was significantly smaller, surgical treatment would likely have been sufficient. Ordinarily, neither radiotherapy, chemotherapy nor a stoma would have been necessary. In Professor Clarke’s opinion, if he is correct that the cancer was at stage 3, the Plaintiff would have undergone the same treatment as was actually administered, namely, total neoadjuvant therapy with chemotherapy then chemoradiation before resection.
The concrete difference between their positions is whether, as at the August 2022 Consultation, the tumour had penetrated the bowel wall and/or involved regional lymph nodes. Associate Professor Pendlebury says neither. Professor Clarke says at least one, and probably both. They take different paths in arriving at their conclusions.
Both expert oncologists reason forwards and backwards from the available data, though they do not seem to agree on which sets of data are most valuable. Associate Professor Pendlebury reasons forwards from the negative examination findings and the interval during which the Plaintiff did not present to his doctor and backwards from population growth and delay data. Professor Clarke reasons forwards from the Plaintiff’s symptomatology as at the August 2022 Consultation and backwards from the tumour’s observed behaviour since diagnosis.
In her analysis, Associate Professor Pendlebury proceeded on the assumption that a rectal examination had been performed and revealed nothing. That error was corrected during cross-examination, when Mr Hutchings asked Associate Professor Pendlebury to proceed on the assumption that no internal examination had been performed. That change did not cause Associate Professor Pendlebury to change her opinion.
Associate Professor Pendlebury considers that, with diagnosis in 2022 or early 2023, the colostomy before commencing chemoradiotherapy would not have been required. Professor Clarke was more tentative. In his opinion, earlier diagnosis would only have probably reduced the likelihood of a permanent stoma.
Associate Professor Pendlebury considers that the cancer progressed to stage 3B by February 2023, though it would have been less “bulky” than when it was diagnosed in May 2024. By February 2023, treatment would have been total neoadjuvant therapy followed by surgery, but without a defunctioning colostomy before treatment and with a temporary diverting ileostomy at the time of surgery.
Professor Clarke considers that, by February 2023, the cancer would have been locally advanced, with significant local adenopathy and the same histology as was found upon diagnosis. He considers that it would have required the same treatment regime as was eventually administered.
Whilst the oncology experts seemingly agree that, by February 2023, the cancer had advanced, the dispute, as at that date, reduces to outcome: had the cancer been diagnosed in February 2023, would the cancer have perforated the bowel wall, would it have recurred, and would the Plaintiff have a temporary, rather than permanent, stoma.
Resolving the difference between these two highly experienced experts, each of whom I found to be a model witness, is a difficult and nuanced exercise.
Associate Professor Pendlebury’s reasons for her opinion that the cancer was stage 1 as at the August 2022 Consultation are as follows:
the Plaintiff did not raise his symptoms with a GP for over a year after the August 2022 Consultation. Associate Professor Pendlebury would expect that a locally advanced cancer would produce constant symptoms over that time. It did not;
rectal bleeding is the most common indication for colonoscopy, and cancer is found in fewer than 10% of such cases. The Plaintiff’s symptoms did not equate to a locally advanced cancer;
the mean interval for progression from T2 to T3 and T4 is in the order of 485 days. Working backwards from May 2024 places the cancer at T2 in August 2022;
only 4 of 11 nodes were involved even at the time of surgery in 2025. The risk of nodal involvement for a T2 high-grade cancer with lymphovascular invasion is 41.5%. On the balance of probabilities the nodes were not involved;
30 to 40% of mucinous carcinomas with signet ring cells present at stages 1 or 2, compared with under 10% for pure signet ring carcinoma. Nodal involvement is 50% in the former, and 75% in the latter. Early-stage presentation was accordingly a real possibility here; and
Professor Clarke’s suggestion that the cancer was always stage 3 is nonsensical. It must have progressed from an earlier stage.
Professor Clarke’s reasons for concluding that the Plaintiff’s cancer was, as of the August 2022 Consultation, stage 3, are as follows:
tenesmus is an indicator of locally advanced disease. In his experience, it is uncommon for chronic tenesmus to be present in early rectal cancer. Since the Plaintiff had tenesmus in around September 2021, it is unlikely that the cancer was in an early stage;
the Plaintiff’s need to sit on a ring cushion indicated whilst driving that the tumour was pressing on local nerves. Professor Clarke maintained this view even after it was pointed out to him that the Plaintiff first started using the ring cushion in September 2023, over a year after the August 2022 Consultation. He maintained that his conclusion was nevertheless supported by the continuing tenesmus and preceding 12 months of rectal bleeding;
Professor Clarke suspected that the Plaintiff did not mention his bowel issues at medical appointments or seek further advice because he was frightened by the symptoms. In this regard, Professor Clarke relied on the Plaintiff’s text exchanges with Mrs Peterkin and on the history taken by Professor Fox (whose evidence is relevant to quantum, which I will not address in this judgment); and
the nodes were large both on MRI and at resection. Given the cancer’s slow growth since diagnosis, they would already have been involved in August 2022.

The Plaintiff maintains that, had the existing tumour been diagnosed shortly after the 23 August 2022 consultation, it would have been considerably smaller and could have been managed in a way that would have produced a better clinical outcome. The Defendant argues that, had he discovered the tumour during the consultation, it would have made no difference because the tumour was likely already large and would not have been receptive to treatment that would have led to a clinically better outcome.
Associate Professor Pendlebury’s opinion is biological and clinical. Her reasoning is distilled as follows:
mucinous rectal cancers are generally high grade, meaning (relevantly) that the cancer’s cells divide rapidly. The pathologist reported the tumour as poorly differentiated and high grade;
the post-operative course demonstrates that point. Surgery occurred in February 2025 and the tumour was found to have recurred by December 2025. The Plaintiff’s cancer recurred at the anastomosis (the exact location where the ileostomy was reversed), which Associate Professor Pendlebury regarded as uncommon;
the Plaintiff suffered acute obstruction of his ureter within months of definitive surgery and required ureteric stenting weeks thereafter. Associate Professor Pendlebury considered that this is not the behaviour of an indolent disease;
the cancer recurring in the pelvis and peritoneum reflects the pattern of the subtype, not slow growth. Associate Professor Pendlebury observed that patients with mucinous cancers frequently die of bowel obstruction and intra-abdominal misadventure rather than metastatic disease. The absence of distant spread does not make the rapid recurrence within the abdomen any less significant;
increase in tumour volume is not one cancer cell secreting ever more mucin. Rather, the increased volume of mucin implies a commensurate increase in the volume of the cancer producing it; and
the tumour’s failure to respond is due to the absence of an effective drug and also the efficacy of the tumour’s resistance mechanisms, not slow cell division.
Professor Clarke considered that the tumour is indolent, or “low grade”. I distil his reasoning as follows:
the Plaintiff remains alive even though the tumour has largely failed to respond to any treatment. The Plaintiff has lived well beyond the 14-month median survival time for mucin-secreting colorectal cancer;
a mucinous mass may be largely fluid, “a bag full of liquid with cancer cells on the rim”. The apparent volume of a mucinous mass may reflect mucin accumulation rather than cell division. A biopsy would show fewer cancer cells undergoing mitosis;
both chemotherapy and radiotherapy target cells which divide. The tumour’s failure to respond to treatment is evidence that only a relatively small percentage of its cells are dividing;
aggressive colorectal cancers spread to the liver, lung, bone or brain. The Plaintiff’s cancer has not;
during the conclave, Professor Clarke added that tumour growth, particularly in mucinous tumours, is Gompertzian, meaning that it slows down as the tumour becomes larger; and
a rapidly growing cancer causes problems over the course of months, whereas the Plaintiff’s has caused problems over months to years.
In attempting to grapple with the size of the tumour as at the date of the Plaintiff’s consultation with the Defendant, Associate Professor Pendlebury consulted published doubling times for primary colorectal cancer. The most rapidly growing such cancers double in size every 100 days, while the slowest double every 1,000 days. As Associate Professor Pendlebury regards the Plaintiff’s tumour as a high-grade cancer, a fairly rapid doubling time of 211 days was adopted. Using the May 2024 dimensions (6 cm in length with a 15 mm depth of invasion), she worked backwards. She approached the question on the basis of a mean doubling time of 211 days, T stage progression in 78% of patients over a 150-day delay, and a mean time to progression from T2 to T3/T4 of 485 days. She considered that the rate of locally advanced disease at colonoscopy rises from approximately 0.6% at under six months to 1.2% at 10 to 12 months and 2.1% beyond 12 months. During her examination in Court, she referred to the medical literature on doubling times across a range of cancers, distinguishing the subclinical growth phase, the detectable and potentially alterable phase, and the late phase.
I note that, although Associate Professor Pendlebury initially stated that the delay between the August 2022 Consultation and diagnosis was 411 days, this was caused by an arithmetical error. The delay was in fact 644 days.
Professor Clarke disagreed with Associate Professor Pendlebury’s conclusions. He emphasised that radiological doubling time measures two-dimensional size, which may not reflect what is happening at the cellular level. For this reason, he preferred the individual’s natural history to a population model, saying that such a history means “[y]ou don’t need estimated doubling times, you’ve got the person and you’re seeing how it changes”. He stated that applying the medical literature to an individual whose natural history is known “becomes a little bit irrelevant”. In his opinion, if the tumour were doubling at the rate proposed by Associate Professor Pendlebury and were unresponsive to treatment, it would by now be “huge”.
Professor Clarke did, however, accept that if there was a breach in the tumour while it was being surgically removed, cancer cells could spill into the abdomen and lead to local recurrence.

However, the question is still to be determined “in the light of all relevant circumstances”: s 5D(3)(a) of the CLA.
The Plaintiff points out that the Defendant conceded that if the Plaintiff had reported bloating, constipation, bleeding and urgency, he would have considered a differential diagnosis, including colorectal cancer. The Plaintiff submits that those symptoms, and their duration, would have been provided if the Defendant had asked him additional questions. Upon receiving them, the Plaintiff submits, the Defendant would have referred him to a specialist. The Plaintiff submits that Dr Hamilton’s referral for a colonoscopy is what caused him to take his symptoms seriously.
The Defendant contends that the Plaintiff has failed to establish that a specialist was available for him to see and, even if one were available, it cannot be demonstrated that he would have acted on the referral.
He further argues that speculation about how the Plaintiff would have responded to an earlier diagnosis is unnecessary. He did not act on Dr Etemad’s referral to Dr Hamilton in October 2023. The Plaintiff’s own evidence, the Defendant submits, was that he had been exhausted and close to burning out until he commenced employment at Fairfield City Council in March 2024. This led him to defer his health concerns. It was only in February 2024, the second time he saw Dr Etemad, that he acted on the referral, and then only after Dr Etemad had urged him, as her notes record, to contact Dr Hamilton “ASAP”.
An additional issue is the time between seeing a specialist and the colonoscopy procedure. Associate Professor Ho’s evidence was that COVID-19 affected Campbelltown Hospital, as it did “many hospitals in the west and southwest of Sydney”. This caused a significant backlog and a patient in the Plaintiff’s position would have waited approximately 18 months before a colonoscopy.
The Defendant claims that Associate Professor Ho’s evidence is determinative.
The Plaintiff submits that, even if Dr Hamilton would not have performed the colonoscopy within a month in late 2022 (as it may not have appeared sufficiently serious for such an expedited procedure), Mrs Peterkin would not have tolerated a substantial delay. While Mrs Peterkin did not see any need urgently to investigate the Plaintiff’s symptoms until the appointment with Dr Hamilton, after that appointment, she canvassed obtaining a colonoscopy sooner than the one-month period Dr Hamilton could accommodate. The Defendant points out that this means the colonoscopy would have been performed after February 2023, by which time the oncology experts agreed the tumour would have progressed to T3.
I consider these issues in detail below.

The task of determining when, in the counterfactual scenario, the Plaintiff would have had a colonoscopy following his consultation with the Defendant in August 2022 draws parasitically on what in fact occurred when he did receive such a referral in October 2023. That is the most reliable predictor of the Plaintiff’s conduct. It is for this reason I reject the September 2022 date provided to the oncology experts.
On 8 October 2023, the Plaintiff saw Dr Etemad and reported rectal bleeding several times a week without pain on defecation. Dr Etemad is said to have observed a “small haemorrhoid” and referred him to Dr Hamilton “for an opinion and management of rectal bleeding ([haemorrhoid]?)”.
Despite obtaining this referral, the Plaintiff did not act upon it. He cited a range of competing priorities which led him to deprioritise his own health in favour of other stressors.
The Defendant points out that the Plaintiff did not report his abdominal symptoms when attending medical appointments between the August 2022 Consultation and his October 2023 consultation with Dr Etemad. Indeed, he submits, the Plaintiff did not even report those symptoms to his wife in that period.
On 22 February 2024, the Plaintiff again consulted Dr Etemad. During that consultation, Dr Etemad advised the Plaintiff to see Dr Hamilton as soon as possible, telling him that a colonoscopy was needed to rule out polyps, cancer or haemorrhoids, and gave him a second referral. The practice records show that the referral was printed again on 7 March 2024, seemingly at the Plaintiff’s request.
Dr Etemad’s evidence was that she chose Dr Hamilton because he was new to the area, was likely to be available without a long waiting list, and worked in the public system, which mattered because the Plaintiff had no private health insurance. For that reason, Dr Etemad expected an appointment within two to four weeks of the October 2023 referral, with a colonoscopy to follow in about a month if the specialist regarded the case as serious, or in up to 12 months at Campbelltown Hospital if not.
The evidence establishes that the Plaintiff first attended Dr Hamilton on 7 March 2024. On that date, the Plaintiff consented to a colonoscopy, with or without banding of haemorrhoids. Dr Hamilton’s referral is dated 7 March 2024 and recommends admission on 8 March at category A (i.e. within 30 days). After an assessment by the director of surgery, the Plaintiff was downgraded to category B. That decision included the note “no critical symptoms in a 40-year-old”. A letter of 2 May 2024 reveals that Dr Hamilton asked for an earlier listing, citing pencil-shaped stools, PR pain disturbing sleep and persistent tenesmus. The case was restored to category A, and the colonoscopy followed 13 days later.
At a further consultation with Dr Etemad on 8 May 2024, the Plaintiff reported that he was still bleeding and that his symptoms were unchanged, but that he had scheduled an appointment with Dr Hamilton. On 15 May 2024, the Plaintiff attended Dr Hamilton at Campbelltown Hospital. A digital examination revealed a hard mass 10 cm from the anal verge, and the colonoscopy found a 6 cm mass.
The reasons why the Plaintiff did not act upon the referral provided to him in October 2023, which I have touched upon above, were, unsurprisingly, explored during his cross-examination. He acknowledged that he had not prioritised his health, but had placed his wife, their daughter and his father ahead of it. His father’s business difficulties and mental health were a particular source of stress. He did not accept that the Defendant’s diagnosis gave him “confidence” not to pursue the matter for 18 months.
Reading between the lines, I infer that when the Plaintiff saw Dr Hamilton on 7 March 2024, he had lost his referral and contacted Dr Etemad’s practice to obtain a copy of it to provide to Dr Hamilton’s reception staff.
Based upon the Plaintiff’s actual conduct, there is no reason for me to assume that, had he received a referral from the Defendant on 23 August 2022, he would have acted upon it immediately. In addition, I must engage in some degree of speculation as to, (a) whether any such referral would have been made to Dr Hamilton or to some other specialist (it is unclear whether Dr Hamilton worked at Campbelltown Hospital in August 2022), and (b) whether the same stressors that caused the delay from October 2023 were in existence in August 2022.
Three distinct periods emerge from the actual delays:
8 October 2023 to 22 February 2024, which involved around 137 days of inaction by the Plaintiff;
22 February 2024 to around 7 March 2024, a two-week period between the second referral and the Plaintiff seeing Dr Hamilton; and
7 March 2024 to 15 May 2024, a delay of 69 days attributable to the hospital downgrading the Plaintiff’s category.
Applying these delays to the period following the Plaintiff’s consultation with the Defendant, I prefer the February 2023 counterfactual to the November 2022 counterfactual. I do so for the following reasons:
if the Defendant properly interrogated the Plaintiff during this consultation, I find that the Plaintiff would have communicated his lengthy period of rectal bleeding and tenesmus. That is not because of his evidence of how he would have acted, but because of his readiness to make concessions in cross-examination and the fact that he was forthcoming with Dr Etemad when she asked questions at the 8 October 2023 consultation. I consider that the seriousness of the disclosed symptoms would have given rise to an immediate referral to a colorectal specialist; and
had the Defendant advised the Plaintiff that those symptoms required he immediately attend a specialist, and adding delays (a) for the Plaintiff’s dilatory conduct, (b) the delay in obtaining a specialist appointment and (c) the delay in obtaining a colonoscopy in the public health system, I find that the Plaintiff would probably have undergone a colonoscopy and been diagnosed with colorectal cancer by about February 2023.
That is also in line with the delay that occurred between 8 October 2023 and 15 May 2024, accounting for 69 days of delay caused by the hospital downgrading the Plaintiff’s category, which I accept cannot be attributed to the Plaintiff. I find that had the Defendant properly probed the Plaintiff and, by that questioning, extracted the long-standing symptoms, there is no reason to believe that the Defendant would not have impressed upon the Plaintiff the need for him to see a specialist, replete with a suitably authored referral. I also accept that Mrs Peterkin would have encouraged him to make the appointment without delay.
There was no evidence presented to the Court that the same factors which delayed the Plaintiff from acting on his referral in October 2023 were present in August 2022, and I cannot conclude they were.

There is a stark difference between the opinions of Associate Professor Pendlebury and Professor Clarke as to whether a diagnosis in February 2023 (as opposed to May 2024) would have made a tangible (or any) difference to the Plaintiff’s life expectancy.
Professor Clarke maintained that, as at August 2022, the Plaintiff’s cancer was already at stage 3, that total neoadjuvant therapy would not have worked very well, and that even a diagnosis at that time would have left the Plaintiff “in the same circumstance as he is now, albeit with an earlier diagnosis”. Professor Clarke considered that an earlier diagnosis would have made the Plaintiff “appear to live longer”, but with the same outcome. During the concurrent expert evidence, Professor Clarke stated that “this cancer was always going to behave badly”.
As at February 2023, Professor Clarke’s opinion is that the cancer would have been locally advanced (stage 3) with the same histology, albeit “probably a bit smaller”, and would have required the same treatment, and that the Plaintiff’s life expectancy would have been no different.
Associate Professor Pendlebury’s opinion is that, on a diagnosis in February 2023, the cancer would have been categorised as cT3N1M0, stage 3B. Treatment would have been total neoadjuvant therapy followed by surgery, without a pre-treatment colostomy and with a temporary ileostomy. The 10-year survival rate would have been 46%, which she equated to a median survival of the order of nine years from February 2023. Perforation of the bowel “would likely not have occurred”, and she would have expected recurrence, with distant metastatic disease, at about the five-to-six-year mark.
The experts’ opinions as to the Plaintiff’s present prognosis broadly converge. Professor Clarke described the median survival for mucin-secreting colorectal cancer by reference to an article entitled “Mucinous histology” (2009) 100 British Journal of Cancer. If that article states a median for advanced (stage 4) disease, its natural starting point is the onset of stage 4. On the evidence, that occurred in about December 2025. Measured from that date, the Plaintiff is some 10 months into, rather than beyond, the median. On any basis, the experts consider that the Plaintiff’s death is likely to occur between mid-2027 and September 2027.
I find that, if diagnosed in about February 2023, the cancer would have been stage 3B. The Plaintiff would have received neoadjuvant therapy followed by resection.

As the Defendant conceded that the Plaintiff’s full symptoms and history, if disclosed, would require referral “pretty urgently” to a specialist, I find that the Defendant would have referred the Plaintiff to a colorectal surgeon or gastroenterologist by a letter recording the Plaintiff’s symptoms. Such a referral would have been categorised as category B (discussed below).
Each party called evidence from a gastroenterologist as to the time it would have taken for the Plaintiff to obtain a colonoscopy after referral. There was a significant disparity between the estimates of Dr Sethi, for the Plaintiff, and Associate Professor Ho, for the Defendant.
Both specialists agreed that the category they would ascribe to a patient, in terms of priority, depended upon the nature of the referral. That stands to reason. Patients classed as category A are to be seen within 30 days, category B within 90 days, and category C within 365 days. Those categories are also referred to as categories 1, 2 and 3. Both gastroenterologists put the referral at category B. Associate Professor Ho said that the NSW outpatient guidelines would classify a referral framed as haemorrhoids (for a patient aged 39 or under, without a positive faecal occult blood test, presenting with rectal bleeding and a change of bowel habit) as category C, but that in his own practice he classified rectal bleeding as category B. However, even with six months of bleeding, Associate Professor Ho would go no higher than category B.
Dr Sethi would likewise have classified the Plaintiff as category B. If the GP’s referral had indicated a concern about cancer, he would have seen the patient within 30 days (category A) and expedited the colonoscopy. Dr Sethi stated that specialists in the public system are guided by the GP’s referral, with category A patients to be seen within 30 days, category B within 90 days and category C (the same as category 3) within 365 days.
Dr Sethi’s evidence was that the wait for a category 2 referral in August 2022 would be “usually within the 90 day[s] … around 60 to 70 days on average”, and for category 3 “around 5 to 6 months”, in the public system. He described a wait of 18 to 24 months as a “doomsday”, “hyperbolic” scenario. He practised at Ingleburn, near Campbelltown, but ceased practising there in about January 2022, and there was only a “slight” post-COVID backlog in his district.
Associate Professor Ho’s evidence was that the wait for a category 2 procedure at Campbelltown in 2022 was 18 months, because of the COVID-19 backlog. He stated that the current category 2 wait is 476 days. He runs the only public general gastroenterology clinic at Campbelltown.
Set against these opinions is the Plaintiff’s actual pathway in 2024, which was substantially quicker than the wait identified by Associate Professor Ho and consistent, to a much greater degree, with the evidence of Dr Sethi. Admittedly, Dr Sethi did not practise at Campbelltown, but nearby, and it could readily be accepted that by late 2023 the COVID-19 backlog may have attenuated. What remains unexplained is Associate Professor Ho’s evidence that the category 2 wait for a colonoscopy in 2026 is 476 days. It is difficult to understand how the Plaintiff obtained a colonoscopy far more quickly than Associate Professor Ho’s estimate would suggest.
I am not prepared to disregard the circumstances and time frame in which the Plaintiff obtained a colonoscopy after his initial consultation with Dr Hamilton on 7 March 2024. But for the recategorisation, there is no reason to believe that the Plaintiff would not have received his colonoscopy in April 2024 rather than May 2024. For this reason, I prefer the evidence of Dr Sethi and adopt his estimate of 60 to 70 days in the public system.
A diagnosis some months later than February 2023 would not change the stage. Whether it would change the risk of perforation depends on bulk, which I address below.

As already stated, if a diagnosis had occurred in February 2023 or shortly thereafter, both experts agree that the cancer would have been stage 3. At that point, Associate Professor Pendlebury estimates that the Plaintiff would have had a 46% chance of 10-year survival. The difference between her median survival of about nine years from February 2023 and her present prognosis rests on the proposition that the early recurrence was caused by a perforation during the February 2025 operation, which would not have occurred at an operation in 2023.
That, in turn, depends on a finding that there was such a perforation during the February 2025 operation. Neither expert was involved in the operation or has direct knowledge of it, and the surgeon who performed the operation, Dr Hamilton, did not give evidence.
The operation on 20 February 2025 began laparoscopically and was converted to a laparotomy. It comprised a reversal of the colostomy, an ultra-low anterior resection and a loop ileostomy. Dr Hamilton performed the operation with four assistants. The Plaintiff was discharged on 28 February 2025. The hospital nursing records “uncomplicated surgery”.
On 11 March 2025, Associate Professor Santos reported on the resection specimen. His report states that “[t]here is a small defect in the specimen distally. The defect is iatrogenic in nature.” The report also notes that “[t]here is a disrupted area in the specimen … The mucosa and the wall of this area contains malignant cells and mucinous material. The disrupted area happened intra-operatively.”
Associate Professor Pendlebury’s evidence was that perforation is an established risk of rectal cancer surgery (less than 10% in the modern era), and that the risk of early pelvic recurrence following perforation is about 9% where radiotherapy has been delivered. Perforation reduces five-year survival from about 67% to about 41%. Associate Professor Pendlebury considered it more likely than not that the perforation caused the pelvic recurrence, because tumour was present at the site of the perforation, and that it contributed significantly to the early pelvic relapse. By contrast, she considered that a perforation would have been less likely following a February 2023 diagnosis, because the tumour would have been less bulky.
Professor Clarke had not considered the surgical report before giving evidence, but he accepted that “it sounds like it was a tough operation because of fibrosis and things, so it’s possible that there was a breach”. He agreed that, if there was a breach, cells could spill and, despite washout, could cause local recurrence. His substantive view nevertheless remained that the recurrence reflected the tumour’s local avidity.
The evidence as to whether the bowel was perforated during the February 2025 operation points in both directions. I am satisfied, however, on the basis of the pathologist’s report, which was made from the specimen itself, that a perforation occurred. Although the pathologist asked the surgeons to “please correlate” his opinion that the defect was iatrogenic, the surgeons do not appear to have done so.
On balance, I accept the pathologist’s opinion, taken together with the evidence of Associate Professor Pendlebury and Professor Clarke’s acceptance that, in a tough operation, it is possible that a breach occurred.
I can only take that perforation into account if I am satisfied that the delay in the operation, from about February or March 2023 to February 2025, increased the risk of the bowel breach that occurred. The delay otherwise merely changed the date of an operation that would have happened anyway, and the risk of the breach would have been the same on either date. If that were the case, the delay did not in fact increase the risk of harm. Here, Associate Professor Pendlebury’s opinion that a perforation probably would not have occurred at an operation in 2023 is significant.
As with the evidence as to whether a perforation occurred, the evidence as to an increased risk points in both directions. Associate Professor Pendlebury bases her opinion that a less bulky tumour would probably not have been perforated on literature associating perforation with more advanced tumours. That literature connects perforation risk to advancing T-stage, but the tumour would have been T3 on both dates, so her opinion ultimately comes down to bulk alone. I am satisfied that Associate Professor Pendlebury’s opinion is uncontradicted by any contrary expert opinion on this point, and that it accords with the more general proposition that large tumours carry greater operative risk.
I am satisfied that the harm would have been less likely to occur had the operation occurred in the first quarter of 2023

Peterkin v Tadros

At a glance

Court

Decision date

Before

Catchwords

Source

Catchwords

Judgment

JUDGMENT

Introduction

Issues for determination

Procedural history

Background

Evidence

The August 2022 Consultation

The Plaintiff’s cross-examination during his evidence on commission

The Defendant’s evidence

The Defendant’s credibility and reliability

Defendant’s concessions of general principle

Findings of fact in relation to the August 2022 Consultation

Duration of the Plaintiff’s symptoms

Haemorrhoid history

Evidence concerning a digital rectal examination

The reported protruding lump

Urgency and tenesmus

Length of the consultation

Whether the Plaintiff was told to return the next day

Findings

The evidence of Dr Etemad

22 February 2024 consultation with Dr Etemad

The expert general practitioners

Whether a haemorrhoid was visualised

Duty of care

Section 5O: The standard of care and peer professional opinion

Applicable principles

Section 5O(2): Rationality

Determination

Breach of duty

The risk of harm: identification and characterisation

Sections 5B(1)(a) and (b): Foreseeability and significance

Sections 5B(1)(c) and (2): The response of a reasonable person

The pleaded precautions

Findings on the particulars of negligence

The expert oncologists

The academic literature

Discussion of Associate Professor Pendlebury’s qualifications

Areas of agreement

The biology of mucinous rectal cancer

Diagnosis, pathology and staging as at May 2024

Natural history and presence of the cancer

Definition of “locally advanced”

Present condition

The expert oncologists’ disagreement

The Plaintiff’s tumour as at August 2022

Would an earlier diagnosis have led to a better outcome?

Findings

Causation

Stage of disease at the counterfactual dates

Section 5D(3): What the Plaintiff would have done

Loss of life expectancy

Oncology evidence on life expectancy

Whether the Plaintiff would have acted upon a referral

Diagnosis in February 2023

Evidence concerning the time for the Plaintiff to obtain a colonoscopy

Life expectancy if diagnosis had occurred in early 2023

Conclusion

Sections 5D(1)(b) and (4): Scope of liability

Contributory negligence

The pleaded particulars

Section 5R: The standard of care

Orders

Parties

Legislation Cited (2)

Cases Cited (38)