Lower liver cancer risk with antiviral therapy in chronic hepatitis B patients with normal to minimally elevated ALT and no cirrhosis

For chronic hepatitis B (CHB), alanine aminotransferase (ALT) >= 2 x upper limit of normal (ULN) is often used as a major criteria to initiate treatment in absence of cirrhosis, though patients with lower ALT may not be free from future risk of hepatocellular carcinoma (HCC). We aimed to examine the effect of antiviral therapy on HCC incidence based on ALT levels. We performed a retrospective study on 3665 patients consisting of United States and Taiwanese REVEAL-HBV cohort who were consecutive, treatment-naive, noncirrhotic CHB patients aged >= 40 years. Patients were categorized by ALT cutoffs (>= 2 x ULN vs <2 x ULN) and subgrouped by treatment status. Kaplan-Meier and Cox proportional hazards models were used to calculate cumulative incidence and hazard ratio (HR) of HCC adjusting for REACH-B scores. A total of 202 patients developed HCC. Antiviral treatment significantly reduced HCC risk: HR 0.24, 95% confidence interval 0.10-0.58; P=0.001. HCC incidence per 100,000 person-years was significantly higher in untreated versus treated patients, even for those with ALT <2 x ULN: 314.46 versus 0 per 100,000 person-years, P=0.0042. For patients with Hepatitis B Virus (HBV) Deoxyribonucleic Acid (DNA) >= 2000IU/mL, the number-needed-to-treat (NNT) were 15 and 14 to prevent 1 incident HCC at year 10 for patients with ALT <2 x ULN and >= 2 x ULN, respectively. After adjustment by REACH-B score, antiviral treatment significantly decreased HCC incidence even in patients with ALT <2 x ULN. NNT to prevent 1 incident HCC after 10 years of therapy was low (14-15) in patients with mildly elevated HBV DNA >= 2000IU/mL regardless of ALT levels.