Abstract P5-15-01: Lamivudine Prophylaxis during Adjuvant Chemotherapy in Breast Cancer Patients with Hepatitis B Surface Antigen
Authors: Lee H-J , Kim JH , Im S-A , Kim D-Y , Keam B , Lee JH , Kim YJ , Han S-W , Oh D-Y , Jeong S-H , Yoon JH , Kim T-Y , Bang Y-J. 
Published: April 2011

Background: Reactivation of hepatitis B virus (HBV) in inactive hepatitis B surface antigen (HBsAg) carriers receiving cytotoxic chemotherapy is a well known complications resulting in hepatic dysfunction. Lamivudine has been reported to have a role in controlling HBV reactivation during chemotherapy. Our study aimed to report the role of lamivudine prophylaxis in breast cancer patients undergoing adjuvant chemotherapy. Methods: We retrospectively reviewed medical records of 3530 patients with stage 1-3 breast cancer who received neoadjuvant and/or adjuvant chemotherapy from January 2000 to December 2009. One hundred seventy-one HBsAg positive patients with normal baseline liver function were identified. Patients who received lamivudine before the first day of chemotherapy were regarded as lamivudine prophylaxis group and the others as non-prophylaxis group. Hepatotoxicity was assessed according to Common Terminology Criteria for Adverse Events (CTCAE, version 3.0). HBV reactivation was defined as an increase in HBV DNA levels of 10-folds or more when compared with baseline level or absolute increase of HBV DNA level that exceeded 200x 106 IU/ml or positive sero-conversion of HBV DNA. The efficacy of lamivudine prophylaxis was evaluated with grade of hepatotoxicity and HBV DNA levels during and after adjuvant chemotherapy.

Results: Of 171 patients, 70 patients received lamivudine prophylaxis and 101 patients did not. Median age of control group and study group were 45 years (range, 29-72) and 46(range, 29-67) (p=0.892). Median follow up duration was 48.5 months. Sixty-seven of 101 patients in non-prophylaxis group and 68 of 70 patients in prophylaxis group received anthracycline containing chemotherapy (p=&lt;0.0001). Two (2.9%) patients in prophylaxis group and 13 (12.9%) patients in non-prophylaxis group experienced grade 2 or higher hepatotoxicities (p=0.027). HBV reactivation tend to occur more frequently in non-prophylaxis group compared with prophylaxis group (6.9% vs. 1.4%, p=0.143). One patient in non-prophylaxis group died of fulminant hepatitis after HBV reactivation. Interruption rate of adjuvant chemotherapy was higher in non-prophylaxis group compared with prophylaxis group (9.9% vs.1.4%, p=0.028). Among patients treated with anthracycline containing chemotherapy, the frequency of grade ≥2 hepatotoxicities (2.9% vs. 13.4%, p=0.026) was significantly higher in non-prophylaxis group; HBV reactivation (1.5% vs. 7.5%, p=0.115) tend to be higher in non-prophylaxis group. In patients receiving non-anthracycline containing chemotherapy, lamivudine prophylaxis did not make difference in hepatotoxicities or HBV reactivation.

Conclusion: Fewer hepatotoxicities occurred in lamivudine prophylaxis group with less frequent interruption of scheduled chemotherapy. Lamivudine showed tendency to reduce HBV reactivation in breast cancer patients receiving cytotoxic chemotherapy. Lamivudine prophylaxis should be considered in HBsAg positive breast cancer patients who are candidates of neoadjuvant and/or adjuvant chemotherapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-15-01.