Statement of Principles concerning malignant neoplasm of unknown primary site (Balance of Probabilities) (No. 104 of 2022)

The central concept is “malignant neoplasm of unknown primary site”, defined in section 7(2) as a histologically confirmed metastatic malignant neoplasm for which the primary tumour site cannot be identified after a complete history, physical examination, and appropriate diagnostic investigations. The definition excludes specific tumour types: haematolymphoid tumours (including non-Hodgkin and Hodgkin’s lymphoma), malignant melanoma, and mesenchymal tumours (including soft tissue sarcoma). Note 1 to the definition lists histological types that are included, such as adenocarcinomas, squamous cell carcinomas, neuroendocrine tumours, and poorly differentiated or undifferentiated neoplasms. The ICD-10-AM code is C80, but the instrument’s own definition governs.

“Relevant service” is defined in the Dictionary (Schedule 1) as: (a) eligible war service (other than operational service) under the VEA; (b) defence service (other than hazardous service and British nuclear test defence service) under the VEA; or (c) peacetime service under the MRCA. This means the instrument does not apply to operational service (combat service) or hazardous service, which are covered under a separate class of Statements of Principles using the reasonable hypothesis standard. This is a threshold limitation: veterans who served in warlike operations may have a different pathway to establishing service connection.

The “factors” in section 9 are the causal conditions. They are exhaustive. Key factors include smoking tobacco products (minimum 20 pack-years, onset within 20 years of cessation), alcohol consumption (minimum 200 kilograms, onset within 40 years of cessation), ionising radiation (cumulative equivalent dose of at least 0.5 sievert to at least one body location, at least 5 years before onset), and infection with specific types of human papillomavirus (HPV) or Epstein-Barr virus, but only for squamous cell carcinoma of unknown primary site of the head and neck or of the inguinal lymph nodes. The factor “inability to obtain appropriate clinical management for malignant neoplasm of unknown primary site” (section 9(7)) applies only to material contribution to, or aggravation of, the condition when it was suffered or contracted before or during (but not arising out of) relevant service (section 10(2)). This factor is a safety valve for cases where the condition existed before service but worsened due to inadequate treatment.

Other important definitions: “one pack-year” equals 20 cigarettes per day for one year or 7,300 grams of smoking tobacco by weight. “Cumulative equivalent dose” is calculated per the ARPANSA Guide, excluding normal background radiation. “Specified human papillomavirus” lists 20 high-risk types (16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 67, 68, 70, 73, 82). “Squamous cell carcinoma of unknown primary site of the head and neck” is defined narrowly to exclude nodes solely in the supra-clavicular region.

The instrument directly affects veterans and members of the Forces who have rendered “relevant service” (as defined) and who are claiming compensation for CUP or death from CUP under the VEA or MRCA. That group includes: veterans with eligible war service (e.g., peacetime service or non-operational deployments), members with defence service (non-hazardous, non-British nuclear test), and members with peacetime service under the MRCA. The instrument does not cover claims from veterans with operational service (e.g., combat) or hazardous service; they would be assessed under a different SoP (reasonable hypothesis) for CUP. The instrument also indirectly affects the dependants of deceased veterans who claim dependency compensation.

Medical and legal professionals are directly affected: medical practitioners who diagnose CUP, prepare reports, and provide evidence on factors (e.g., smoking history, radiation exposure, HPV typing); lawyers and advocates who advise claimants on the likelihood of success and the evidence required; and decision-makers in the Department of Veterans’ Affairs, the Veterans’ Review Board, and the Administrative Appeals Tribunal who must apply the SoP strictly. The Repatriation Medical Authority (RMA) is the maker of the SoP; its members are medical specialists who determine the factors based on sound medical-scientific evidence.

The instrument also affects the health system indirectly: for example, the definition of CUP excludes certain tumours, which may redirect claims to other SoPs (e.g., for non-Hodgkin lymphoma). The high thresholds for smoking and alcohol create compliance burdens for claimants who must reconstruct decades-old consumption patterns, often without contemporaneous records. The ionising radiation factor (0.5 Sv cumulative equivalent dose) is a substantial exposure; most diagnostic medical procedures fall well below that, unless a person has undergone extensive radiotherapy or occupational exposure. The HPV factors apply only to specific anatomical sites, limiting the pool of eligible claimants.

From an economic perspective, the SoP serves as a gatekeeper for compensation expenditure. By specifying high thresholds and latency periods, it reduces the number of successful claims relative to a more generous standard. This has a direct fiscal effect on the Commonwealth budget for veterans’ entitlements. It also creates incentives for claimants to maximise reported consumption or to seek alternative causation theories (e.g., arguing multiple factors cumulatively). The instrument does not allow apportionment of causation among factors; one factor suffices if it meets the thresholds.

The SoP does not create new duties or rights in the general law; it operates within the existing framework of the VEA and MRCA. The key duty for a claimant is to prove, on the balance of probabilities, that at least one factor in section 9 existed and that the factor was related to the person’s relevant service (section 10). This is an evidentiary burden. Claimants have a right to have their claim determined in accordance with the SoP. If the decision-maker fails to apply the SoP correctly, the claimant has rights of internal review and external merits review (Veterans’ Review Board, Administrative Appeals Tribunal) and ultimately judicial review.

For the decision-maker (the Repatriation Commission or MRCA delegate), the duty is to apply the SoP strictly. The factors are exhaustive; a decision‑maker cannot find service‑connection based on other causal mechanisms not listed. The instrument provides definitions and calculation methods that the decision‑maker must follow. For example, “pack-year” must be calculated as per the Dictionary note; “cumulative equivalent dose” must be calculated per the ARPANSA Guide.

The SoP also imposes a duty on the RMA to base factors on sound medical‑scientific evidence (section 8). This is a statutory precondition. However, the instrument does not create a right for a claimant to challenge the soundness of the medical evidence underlying the SoP itself (though such a challenge could be made in judicial review proceedings on grounds of unreasonableness or error of law).

A notable right is the ability to rely on a factor that “refers to an injury or disease covered by another Statement of Principles” (section 11). This incorporates by reference the factors from other SoPs. For example, if a factor under section 9(7) (inability to obtain appropriate clinical management) refers to another condition such as depression (which might be a cause of the inability), the claimant can rely on the SoP for that condition to establish the factor. This cross-referencing prevents gaps but also adds complexity.

The factor “inability to obtain appropriate clinical management” (section 9(7)) is subject to a special limitation: it applies only to material contribution or aggravation, not to original causation, where the CUP was suffered or contracted before or during (but not arising out of) relevant service (section 10(2)). This is a narrow application: it allows a claim where service‑related inadequate treatment worsened an existing CUP, but not where service caused the CUP itself.

The SoP is not a penal instrument; it does not create offences or impose fines. Its force is in determining eligibility for compensation. The practical “penalty” for a claimant who cannot satisfy the factors is denial of a pension or other benefit. There is no penalty for making an unsuccessful claim, though there may be cost consequences in tribunal or court proceedings (limited under veterans’ law).

Enforcement of the SoP occurs through the administrative decision-making process. The Repatriation Commission is required to apply it. If a decision-maker does not apply the SoP correctly, the claimant can seek review. The Veterans’ Review Board and the Administrative Appeals Tribunal can set aside or vary the original decision. The Federal Court can quash a decision that involves an error of law, including a misinterpretation of the SoP.

There is a potential for misuse: a claimant might exaggerate smoking or alcohol consumption to meet the thresholds. However, the onus of proof is on the claimant, and decision-makers can scrutinise the evidence. The instrument does not specify evidentiary standards (e.g., whether self-reporting is sufficient). In practice, the RMA’s factors are based on epidemiological evidence; decision‑makers often require corroboration from medical records, personnel files, or family statements.

The SoP also has a “cross‑referencing” enforcement mechanism: if a claimant relies on a factor that refers to another disease (e.g., inability to obtain appropriate clinical management for a condition that is itself subject to an SoP), then the factors of that other SoP must also be satisfied (section 11). This creates a cascading compliance burden.

No criminal or civil penalty provisions exist in this instrument. The only enforcement is the legal requirement for the decision-maker to apply it, which is judicially enforceable.

The SoP is made under section 196B(3) of the VEA. It interacts with the VEA as a whole, particularly Part XIA (which governs Statements of Principles). It repeals the previous SoP for CUP (No. 81 of 2014). It applies to claims under section 120B of the VEA (balance of probabilities standard for certain claims) and section 339 of the MRCA. The MRCA itself is a separate compensation scheme for military members; the SoP harmonises causation rules across both schemes for the relevant service types.

The SoP also interacts with other Statements of Principles. Section 11 expressly provides that if a factor in section 9 refers to an injury or disease that is itself covered by an SoP, then the factors of that SoP apply. For example, the factor “inability to obtain appropriate clinical management” might be linked to an underlying condition like anxiety disorder; the claimant would then need to satisfy the SoP for anxiety disorder to establish the inability. This avoids contradictions and ensures consistency across different conditions.

The definition of CUP refers to ICD-10-AM code C80, but the instrument’s own definition is broader than a pure coding approach. The note to section 7(2) provides a non-exhaustive list of histological types. This means that a claimant with a diagnosis of, say, adenocarcinoma of unknown primary must still meet the histological confirmation and other criteria. The interaction with ICD coding is relatively weak: the code is used for statistical purposes, but the legal meaning is determined by section 7(2).

The SoP does not interact directly with state workers’ compensation laws, since veterans’ entitlements are a federal matter. However, it may affect claims under the Safety, Rehabilitation and Compensation Act 1988 (SRCA) for employees who are not covered by MRCA, but that Act has its own causation provisions not directly linked to the SoP. The SoP also does not affect criminal law, tort law, or private insurance contracts.

One important interaction is with the standard of proof: this SoP applies to claims where the standard is balance of probabilities (non‑operational service). For operational service claims, a different SoP for CUP would apply under section 196B(2) (reasonable hypothesis standard). The RMA may have issued such an SoP; if not, the claim is assessed without a SoP. This distinction creates a two‑tier system where the evidentiary burden on the claimant differs depending on the nature of service.

The instrument is a standalone legislative instrument. It repeals the Statement of Principles concerning malignant neoplasm of unknown primary site No. 81 of 2014 (F2014L01143). That earlier SoP was made under both subsections 196B(3) and (8) of the VEA. The new SoP is made under subsection 196B(3) only; it does not include the “reasonable hypothesis” standard for operational service. The earlier SoP was likely amended from even earlier versions; this is the second iteration.

The instrument commenced on 21 November 2022 (section 2). It was made on 21 October 2022. There is no subsequent amendment mentioned in the text. The instrument includes a definition of “cumulative equivalent dose” that incorporates the ARPANSA Guide as in force on 2 August 2017, freezing a particular version. If the ARPANSA Guide is updated, the SoP would not automatically adopt the new methodology unless amended. The same applies to the ICD-10-AM Tenth Edition (1 July 2017). This freezing of external references can lead to technical obsolescence.

The RMA periodically reviews Statements of Principles based on emerging medical evidence. The change from No. 81 of 2014 to No. 104 of 2022 likely reflects updated epidemiological data. For example, the earlier SoP may have had different thresholds for smoking, alcohol, or radiation, or may have listed different HPV types. Without the earlier instrument for comparison, one cannot identify specific changes. However, the repealing clause signals that the RMA considered the earlier SoP no longer accurate on the basis of sound medical‑scientific evidence.

The instrument does not specify a sunset date. It remains in force until repealed or replaced.

The instrument itself provides no case citations. Statements of Principles are frequently the subject of disputes in the Veterans’ Review Board and the Administrative Appeals Tribunal, and occasionally the Federal Court, on issues such as the correct interpretation of factors, the meaning of “sound medical‑scientific evidence”, and the standard of proof. For example, past cases have considered whether a factor is “related to” service, or whether a claimant’s smoking history meets the pack‑year calculation. However, the specific SoP No. 104 of 2022 has been in force only since November 2022, and it is not possible here to name any cases that have considered it. The absence of cited cases in the source means the analyst must not invent any.

Claimants may challenge the instrument itself on judicial review grounds (e.g., whether the RMA erred in determining the factors based on sound medical‑scientific evidence). The High Court has considered the constitutional validity of the SoP regime (e.g., in the context of the VEA), but no such challenge specific to this SoP is in the instrument. Practitioners should be aware that the definition of “malignant neoplasm of unknown primary site” has been litigated in earlier SoPs; the narrow exclusion of certain tumour types (haematolymphoid, melanoma, mesenchymal) may be contested where a claimant argues their tumour is a variant that should be included.

The cross-referencing mechanism in section 11 has also been litigated: claimants may attempt to use a factor from another SoP that is more generous. The instrument’s clear language prevents that unless the factor itself refers to another disease.

In summary, no specific litigation is recorded in the SoP, but the potential for interpretative disputes remains high.

Several provisions contain traps for the unwary.

First, the definition of “relevant service” excludes operational service and hazardous service. A veteran who served in a theatre of war but whose claim is determined under the balance of probabilities standard (e.g., because they are not claiming for operational service) might mistakenly think this SoP applies. It does not. They would need a different SoP under s196B(2). The instrument applies only to the specific service types listed.

Second, the smoking factor (section 9(1)) is stringent: 20 pack-years. Many veterans may have smoked but not at that level. The calculation of pack-years uses the note: 20 cigarettes per day for 1 year = 1 pack-year; pipe tobacco is converted by weight (1 gram of tobacco = 1 cigarette). Claimants who smoked roll-your-own cigarettes may have difficulty quantifying their consumption. The latency period of at least 5 years before clinical onset and the requirement that onset occur within 20 years of cessation (if ceased) further narrow eligibility. A veteran who quit 25 years ago and develops CUP now cannot rely on smoking.

Third, the alcohol factor (section 9(2)) is extremely high: 200 kilograms of alcohol, equivalent to 20,000 standard drinks. Most moderate drinkers will not meet this. The assumption that alcohol consumption can be calculated based on standard drinks (10g alcohol) may not reflect actual intake. The 40-year window after cessation may capture older veterans, but the cumulative consumption threshold is very high.

Fourth, the ionising radiation factor (section 9(3)) requires a cumulative equivalent dose of 0.5 sievert. Many medical diagnostic procedures deliver much less (a CT scan is about 0.01 Sv). Only repeated radiotherapy, nuclear industry exposure, or nuclear weapons testing would reach this level. The calculation method is per the ARPANSA Guide; that guide may be complex and may require expert reconstruction. The dose must be to “at least one location in the body”, which is a low bar, but the total dose must still be 0.5 Sv.

Fifth, the HPV factors (sections 9(4) and (5)) are limited to specific anatomical sites: squamous cell carcinoma of the head and neck (excluding supra-clavicular nodes) for HPV 16/18 or EBV, and inguinal lymph nodes for any of the 20 specified HPV types. A CUP that presents elsewhere (e.g., in the axillary nodes) cannot use these factors. The claimant must have documented HPV infection, which may require retrospective testing (e.g., PCR on archived biopsy tissue).

Sixth, the “inability to obtain appropriate clinical management” factor (section 9(7)) is not a standalone causation factor. Section 10(2) restricts it to cases where CUP was already present before or during (but not arising out of) relevant service, and the factor applies only to material contribution or aggravation. In other words, it cannot be used to establish that service caused the initial CUP. A common error is to argue that service-related lack of treatment caused the CUP itself; that is not permitted.

Seventh, the cross-referencing in section 11 may require a claimant to satisfy multiple SoPs. For example, if the inability to obtain appropriate clinical management is due to a psychiatric condition, the claimant must meet the SoP for that psychiatric condition. This can create a cascade of evidentiary burdens.

Eighth, the instrument does not define “appropriate diagnostic investigations” for confirming the primary site cannot be identified. This invites conflicting expert opinions. The RMA’s note says “complete history, physical examination and appropriate diagnostic investigations” but does not specify which tests. A claimant whose investigation was incomplete may be told their diagnosis does not meet the definition.

Ninth, the exclusion of melanoma, haematolymphoid tumours, and mesenchymal tumours means that a patient with a metastatic lesion of unknown primary who later is diagnosed with, say, lymphoma, cannot use this SoP. They must apply a different SoP.

Tenth, the instrument applies to death from CUP (section 7(5)), including death contributed to by a terminal event (pneumonia, respiratory failure, etc.). The claimant must still show that the CUP itself was service‑related; the terminal event is not a separate factor.

For a claimant or legal representative, compliance means marshalling evidence to satisfy at least one factor and showing its relationship to relevant service. The evidence required will depend on the factor chosen.

Smoking (section 9(1)): Obtain a detailed smoking history: start age, years smoked, average number of cigarettes per day or grams of tobacco per week. Convert to pack-years using the formula: (cigarettes per day ÷ 20) × years smoked. If the claimant smoked less than 20 per day, the pack-year total may be lower. For pipe or cigar smokers, use the weight equivalency: 1 gram of tobacco = 1 cigarette. Confirm that smoking commenced at least 5 years before clinical onset of CUP. If smoking ceased before onset, ensure onset occurred within 20 years of cessation. Gather corroborating evidence: service medical records, personnel files, statements from family, or contemporaneous purchase records. If no direct evidence, self-reporting may be accepted but weaker.

Alcohol (section 9(2)): Quantify cumulative consumption in kilograms of alcohol. Use the Australian Standard of 10g per standard drink. Calculate: total standard drinks × 10g = grams; then convert to kilograms. Example: 20 standard drinks per week for 20 years = 20 × 10g × 52 × 20 = 208,000g = 208 kg. Ensure consumption commenced at least 5 years before onset, and if ceased, onset within 40 years. Evidence: self-reporting, medical records (e.g., liver function tests, history of alcohol abuse), service records, or family statements.

Ionising radiation (section 9(3)): Obtain a dose reconstruction per the ARPANSA Guide. Identify all sources: medical exposures (radiation therapy, CT scans, nuclear medicine), occupational exposures (e.g., aircraft crew, nuclear worker), environmental exposures (e.g., nuclear test fallout). Exclude normal background. Sum the doses to any single site (e.g., chest, abdomen). If the total reaches 0.5 Sv, document the exposure history and the calculation methodology. Expert evidence may be needed.

HPV/EBV (sections 9(4)-(6)): For head and neck squamous cell carcinoma (not solely supra-clavicular), test the lymph node biopsy for HPV type 16 or 18 (or for EBV by serology or PCR for EBV DNA or RNA). For inguinal lymph node involvement, test for any specified HPV (20 types). The infection must have been present before clinical onset; because HPV infection can be cleared, proof of past infection may require serological testing or detection of viral DNA in the tumour. The factor does not specify latency, but logically the infection precedes the malignancy.

Inability to obtain appropriate clinical management (section 9(7)): This factor is only available for material contribution or aggravation when the CUP existed before or during (but not arising out of) relevant service. Show that the person had CUP before service (or that it arose during service but not from service), and that service‑related factors prevented them from obtaining appropriate treatment (e.g., delayed diagnosis, lack of access to specialist care, refusal of treatment). The claimant must also satisfy the SoP for any underlying condition that caused the inability (e.g., service‑related anxiety).

Document relationship to service (section 10): Each factor must be related to relevant service. For smoking: was the smoking pattern attributable to service conditions (e.g., stress, availability of cigarettes)? For alcohol: same. For radiation: was exposure from service activities (e.g., aircraft crew cosmic radiation, nuclear test participation)? For HPV: service may not be a direct cause, but the weapon/vaccine interaction may be argued. For inability to obtain clinical management: the inability must arise from service (e.g., being stationed remote, service‑related injuries preventing treatment).

Procedural steps: The claim must be lodged with the Department of Veterans Affairs. The claimant should provide a detailed medical report confirming the diagnosis of CUP per section 7(2) (histologically confirmed metastatic, primary unknown after complete investigation). Include the relevant factor evidence and an explanation of how each factor relates to service. If the claim is denied, seek merits review (Veterans’ Review Board, then AAT). Legal representation is advisable given the technical nature of the SoP.

For decision-makers: Apply the SoP strictly. Ensure that the condition meets the definition (exclude listed tumours). Calculate pack-years, alcohol kilograms, and radiation dose per the Dictionary. Verify the anatomical site for HPV factors. Do not consider factors not in section 9. Apply section 11 if a factor refers to another SoP. Document the reasoning.