Abstract: Objective To explore the incidence and risk factors of hepatitis B virus (HBV) reactivation in breast cancer (BC) patients during chemotherapy. Methods From May 2012 to December 2018, 236 BC patients with HBV infection were collected, They were all female patients, with an average age of (48.6±11.0) years. According to whether HBV reactivation occurred during chemotherapy, the patients were divided into a reactivation group and a non-reactivation group. The severity of liver injury in HBV reactivated BC patients was referred to WHO grading standard., T test, chi-square test or rank sum test were used for statistical comparisons based on the data types; Multivariate analysis was used to explore the independent risk factors of HBV reactivation in BC patients. Results In 236 cases of BC patients with HBV infection, 44 cases were reactivated with an incidence rate of 18.6%. Comparing the clinical data of patients in reactivation group and non-reactivation group, the age of reactivation group and non-reactivation group was (43.8±13.2) years and (50.2±9.4) years, with statistically significant difference (t=-7.894, P<0.05). There were 40 cases (90.9%) and 85 cases (44.3%) of HBV-DNA positive patients at baseline in the reactivation group and the non-reactivation group, respectively, with statistical significance (χ²=31.255, P<0.05). There were 18 cases (40.9%) and 11 cases (5.7%) in reactivation group and non-reactivation group, and the difference was statistically significant (χ²=41.104, P< 0.05). The levels of baseline and post-chemotherapeutic ALT, AST, and TBil in the reactivation group were (37.5±5.6) U/L and (64.4±9.5) U/L, (36.0±5.2) U/L and (55.2±7.6) U/L, and (12.3±3.2) μmol/L and (18.4±3.8)μmol/L, respectively, which were significantly different with those of (21.4±3.5) U/L and (42.4±7.8) U/L, (19.2±3.0) U/L and (38.7±6.8) U/L, and (10.7±2.0) μmol/L and (14.6±2.6)μmol/L of the non-reactivation group (t=12.035, 15.022, 18.642, 9.258, 6.028, P< 0.05). Taking the above-mentioned difference data as independent variables and whether HBV-infected BC patients have virus reactivation as dependent variables, the results of multivariate analysis suggested that baseline HBV-DNA positive, discontinuation of antiviral drug, baseline ALT and baseline AST were independent risk factors for HBV reactivation in HBV-infected BC patients (P<0.05). The liver injuries grading I, II, III, and IV in the reactivation group were 3 cases (6.8%), 11 cases (25.0%), 7 cases (15.9%), and 2 cases (4.5%), respectively, which were significantly different with those of 22 cases (11.4%), 13 cases (6.8%), 0(0) and 0(0), in patients of non-reactivation group (χ²=22.069, P<0.05). Conclusion The incidence of virus reactivation during chemotherapy in BC patients with HBV-infection is high. it is necessary to pay attention to the alteration of HBV-DNA and liver function in these patients, and instruct the patients to regularly taking antiviral drugs.

Key words: Breast cancer, HBV infection, Virus reactivation, Multivariate analysis