Hepatitis B surface antigen seroconversion after HBV reactivation in non-Hodgkin's lymphoma.

Reactivation of hepatitis B virus (HBV) can occur in lymphoma patients infected with HBV when they receive chemotherapy or immunotherapy. Prophylactic administration of lamivudine (LAM) reduces the morbidity and mortality associated with HBV reactivation. However, what defines HBV reactivation and the optimal duration of treatment with LAM have not yet been clearly established. HBV reactivation may occur due to the cessation of prophylactic LAM, although re-treatment with nucleoside analogs may sometimes result in hepatitis B surface antigen (HBsAg) seroconversion, which is a satisfactory endpoint for the management of HBV infection. We report a case of HBV reactivation in a 68-year-old HBsAg-positive patient who received rituximab-based immunochemotherapy for follicular lymphoma. HBV reactivation developed following cessation of prophylactic LAM therapy. The patient subsequently received treatment with entecavir (ETV), which led to a rapid and sustained suppression of HBV replication and HBsAg seroconversion. We also appraised the literature concerning HBV reactivation and the role of ETV in the management of HBV reactivation in lymphoma patients. A total of 28 cases of HBV reactivation have been reported as having been treated with ETV during or after immunosuppressive chemotherapy in lymphoma patients. We conclude that ETV is an efficacious and safe treatment for HBV reactivation following LAM cessation in lymphoma patients treated with rituximab-based immunochemotherapy.