Late reactivation of hepatitis B virus after rituximab-containing chemotherapy for mantle cell lymphoma: a case report.

Our study demonstrates that the risk of HBV reactivation in HBsAg-positive patients with undetectable HBV-DNA can occur even after three years from the last administration of rituximab and several months after the withdrawal of prophylactic antiviral therapy in patients with hematological malignancies. This implies that a close monitoring of HBV-related markers including HBV-DNA must continue after the withdrawal of prophylactic NA therapy.