Data were extracted from selected study including demographic data, baseline ALT, viral marker status [HBsAg, anti-HBV surface antibody (HBsAb), HBV envelope antigen (HBeAg), anti-HBV envelope antibody (HBeAb), HBV core antigen (HBcAg), anti-HBV core antibody (HBcAb) and HBV DNA quantitation], rate of HBV reactivation, incidence of hepatitis, severity of hepatitis, chemotherapy disruption, overall mortality, incidence of hepatitis and severity of hepatitis attributable to HBV reactivation, chemotherapy disruption and mortality attributable to HBV reactivation. This evidence concerns the gene GPT and Hepatitis.