Hepatitis B reactivation and timing for prophylaxis

It is known that immunotherapy and cancer chemotherapy may cause hepatitis B virus (HBV) reactivation in hepatitis B surface antigen carriers and inactive chronic hepatitis B patients. Guidelines recommend antiviral prophylaxis regardless of HBV DNA levels to prevent reactivation. We read from the article written by Liu et al that Lamivudine was given inadequate time for antiviral prophylaxis.