Hepatitis B reactivation after withdrawal of pre-emptive lamivudine in patients with haematological malignancy on completion of cytotoxic chemotherapy

Background: The hepatic outcome of hepatitis B surface antigen (HBsAg) positive patients undergoing chemotherapy after withdrawal of pre-emptive lamivudine is unknown. Aims: To examine the occurrence of hepatitis B virus (HBV) reactivation after withdrawal of pre-emptive lamivudine. Methods: Pre-emptive lamivudine was started one week before initiation of chemotherapy in 46 consecutive HBsAg positive patients and continued for the entire duration of chemotherapy. Pre-emptive lamivudine was stopped at a median 3.1 (range 3.0-3.4) months after completion of chemotherapy. Patients were longitudinally followed up after withdrawal of pre-emptive lamivudine. Results: Median time of follow up after withdrawal of lamivudine was 25.7 (range 5.7-75.7) months. Eleven of the 46 patients (23.9%) developed HBV reactivation after withdrawal of pre-emptive lamivudine. Eight of the 16 patients with high pre-chemotherapy HBV DNA (>= 10(4) copies/ml) compared with three of the 30 patients with low pre-chemotherapy HBV DNA (>= 10(4) copies/ml) developed HBV reactivation (50.0% v 10.0%, respectively; p < 0.001). Hepatitis B e antigen positive patients were also more likely to develop HBV reactivation (5/11 (45.5%) v 6/35 (17.1%), respectively; p = 0.041). A high pre-chemotherapy HBV DNA (>= 10(4) copies/ml) was the most important risk factor for HBV reactivation after withdrawal of pre-emptive lamivudine on Cox proportional hazards analysis (relative risk 16.13, (95% confidence interval 2.99-87.01; p = 0.001). Conclusions: HBV reactivation is more likely to occur in patients with high pre- chemotherapy HBV DNA after withdrawal of pre-emptive lamivudine. A more prolonged course of antiviral therapy may be necessary in these patients after completion of chemotherapy in order to reduce post-chemotherapy HBV reactivation.