Hepatitis B and Liver Cancer (Hepatocellular Carcinoma)

Deep Dive

From a western clinical perspective, chronic hepatitis B is a preventable infection and a well‑established carcinogen for hepatocytes. After acu... From a western clinical perspective, chronic hepatitis B is a preventable infection and a well‑established carcinogen for hepatocytes. After acute exposure, immune‑tolerant or immune‑active phases can lead to persistent viremia. HBV’s covalently closed circular DNA stabilizes persistence, and fragments of viral DNA integrate into host chromosomes. Viral proteins—especially HBx—modulate transcription and signaling pathways (e.g., p53, Wnt/β‑catenin), creating selective pressures that favor malignant clones. In parallel, chronic necroinflammatory injury stimulates fibrogenesis; cirrhosis, a preneoplastic state, markedly increases HCC risk. Unlike many liver diseases, HBV can produce HCC without cirrhosis because of these direct oncogenic mechanisms. Epidemiologically, HBV explains about half of global HCC, with the largest impact in regions with early‑life transmission. The REVEAL‑HBV study established a robust, graded relationship between serum HBV DNA and HCC risk, informing modern risk scores. Cofactors such as aflatoxin exposure, heavy alcohol use, metabolic syndrome/NAFLD, and co‑infection with HDV or HCV further elevate risk. Prevention operates on several levels: universal vaccination with a timely birth dose and perinatal prophylaxis have reduced childhood HCC dramatically in Taiwan and other settings. For people with chronic infection, long‑term suppression with high‑barrier nucleos(t)ide analogs reduces necroinflammation, fibrosis progression, and HCC incidence, but residual risk persists, necessitating surveillance. Guidelines recommend semiannual ultrasound, with or without AFP, for all patients with HBV cirrhosis and for high‑risk non‑cirrhotic groups (e.g., Asian men over 40, Asian women over 50, individuals from Africa over 20, and those with a family history of HCC). When small tumors are found early, curative therapies—resection, ablation, or transplantation—offer the best outcomes. More advanced disease may be managed with locoregional approaches (e.g., TACE) and systemic therapies, including immune‑checkpoint inhibitors and anti‑angiogenic agents. Throughout, management of modifiable risks—alcohol abstinence, metabolic control, and food safety to limit aflatoxin—complements antiviral therapy to lower cancer risk.