RESUMO
BACKGROUND: The objectives of this study were to determine the incidence, outcome and risk factors for HBV reactivation in HBsAg positive breast cancer patients while on anthracycline -based adjuvant chemotherapy. METHDOS: We retrospectively reviewed the records of 2,431 patients with early breast cancer who received adjuvant chemotherapy from March 2001 to December 2005. Among these patients, 111 HBsAg positive women were enrolled in this study. RESULTS: Thirty-seven patients (33.3%) developed acute hepatitis, of which 23 (20.7%) were related to HBV reactivation. Univariate analysis showed that an age > or =47 years (p=0.034) and abnormal sonographic findings such as a fatty liver or cirrhotic changes (p=0.034) were associated with HBV reactivation. However, an HBeAg positive status and the use of corticosteroids were not. Multivariate analysis found that no clinical factors could predict HBV reactivation during chemotherapy. All 23 patients who developed HBV reactivation received lamivudine as a therapeutic measure at the time of HBV reactivation. Despite the use of lamivudine, disruption in the chemotherapy protocol occurred in 18 patients (78.3%) and 14 of these patients had premature termination of their chemotherapy. CONCLUSIONS: HBV reactivation occurred in a significant proportion of HBsAg positive patients during adjuvant anthracycline-based chemotherapy. Once hepatitis developed, most patients could not finish the chemotherapy as planned despite lamivudine treatment. Until the risk factors for reactivation are clearly identified, HbsAg-positive patients should begin prophylactic antiviral treatment before initiating chemotherapy.