Liver cancer: the carcinogen roster, synergy, and prevention
Hepatocellular carcinoma's four drivers all round-trip on the liver R19 axis: aflatoxin (RR 6.37), HBV (11.3), HCV (10.4), ethanol (2.2). Aflatoxin×HBV is multiplicative; HBV×HCV (observed 115) sits between the additive (26) and multiplicative (178) modes. De-escalation prioritises HBV. Grade [H] prevention on [F]/[V]/[L].
Circulatory owns the acquired liver cancer. All four HCC carcinogens place on the liver R19 axis at their cited risks; the two cited synergy datasets are bracketed by the kernel's two combination modes — aflatoxin×HBV multiplicative, HBV×HCV between additive and multiplicative — and the de-escalation theorem ranks prevention targets, HBV first.
The full roster on one axis
Hepatocellular carcinoma is the framework-owned acquired liver cancer. Its four IARC Group 1 drivers each place on the liver R19 drive axis by inverting the barrier law at the cited relative risk.
Four drivers, two synergies
Aflatoxin B1 (RR 6.37), chronic HBV (11.3), chronic HCV (10.4) and heavy ethanol (2.2) all round-trip to their cited risks. The two cited synergy datasets fall exactly where the kernel's two combination modes predict: aflatoxin×HBV is multiplicative (§9), while HBV×HCV co-infection (observed RR 115; Korean cohort) sits between the additive mode (26) and the multiplicative mode (178) — more than additive, short of the full product, at fractional position 0.58 in the bracket. This is the framework's prediction that real synergies lie between the modes and approach multiplicative only as the combined drive nears the spinodal.
Prevention: divide, don't subtract; HBV first
For a multiply-exposed liver the combined risk (multiplicative mode) is the product of the driver RRs; removing any one divides it. The de-escalation theorem therefore ranks prevention by driver RR: HBV first (vaccination, nucleos(t)ide suppression), then HCV (direct-acting-antiviral cure achieving sustained virologic response), then aflatoxin reduction (grain storage), then alcohol abstinence. HCV is the cleanest case of the reversibility logic from §20: curing the infection removes the drive, and post-cure HCC risk falls (though it does not vanish in already-cirrhotic livers — consistent with a partly-committed, post-threshold landscape).
Hereditary predisposition — a cross-volume reference
One predisposing route to this same liver cancer is heritable rather than exposure-driven: HFE hereditary haemochromatosis loads the liver with iron, driving cirrhosis and then HCC. It is a monogenic gene-key entity owned by the rare-disease volume (ownership contract), not re-emerged here; on the framework's logic it supplies an endogenous, heritable drive on the very liver R19 axis that the acquired carcinogens above drive exogenously.
Status
Roster placement and synergy bracketing are forced [F] / verified [V] against meta and cohort anchors [L]; the prevention ranking is a prediction [H]; absolute incidence is [O] and the simultaneous four-way combined product is flagged in the battery as [H] ILLUSTRATIVE: the simultaneous 4-way multiplicative product has no anchored cohort; single agents and pairwise synergies are anchored, the full 4-way product is a model extrapolation, not data. Curative and systemic care (resection, transplant, ablation, trans-arterial chemoembolisation, atezolizumab–bevacizumab) is standard of care, not derived here.