A 55-year-old man with a 25-year history of hereditary hemochromatosis (HFE C282Y homozygous) develops hepatocellular carcinoma despite successful iron depletion by phlebotomy. Why does HCC develop even after iron depletion in advanced hemochromatosis?
- A HFE mutations directly activate the EGFR-RAS-MAPK pathway independently of iron accumulation
- B Prior decades of iron-catalysed oxidative DNA damage generate somatic mutations (TP53, CTNNB1, TERT) and epigenetic alterations, while established cirrhosis provides the permissive microenvironment — iron removal does not reverse these changes ✓
- C HFE C282Y homozygosity causes permanent hepcidin deficiency that continues to drive HCC via hepcidin-receptor signalling on hepatocytes
- D Phlebotomy accelerates HCC by mobilising iron-laden hepatocytes into the sinusoids where they undergo malignant transformation
Explanation
In hereditary hemochromatosis, decades of iron overload drive reactive oxygen species production via the Fenton reaction, generating 8-hydroxy-2'-deoxyguanosine (8-OHdG) and other oxidative DNA lesions, promoting somatic mutations in TP53, CTNNB1, TERT and chromosome instability. Simultaneously, iron-induced lipid peroxidation, hepatocyte death and regeneration, and progressive cirrhosis create the permissive microenvironment for HCC. By the time phlebotomy is undertaken in a cirrhotic patient, the 'carcinogenic field' is already established — the mutations, epigenetic alterations, and cirrhotic architecture cannot be reversed by iron removal. This is why HCC surveillance is mandatory even after successful decongestion. HFE does not directly signal to EGFR; hepcidin deficiency is the mechanism of iron overload but hepcidin signalling itself is not hepatocarcinogenic.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
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Written and medically reviewed by the StethoPrep medical team.