Prognostic value of chronic hepatitis B virus infection in patients with breast cancer in a hepatitis B virus endemic area

BACKGROUND: Except for hepatocellular carcinoma, chronic hepatitis B virus (HBV) infection has also been reported to be associated with increased morbidity and mortality of other cancers. However, the impact of chronic HBV infection on the prognosis of breast cancer (BC) remains unclear. Our study aimed to evaluate the prognostic value of HBV infection for BC in an endemic area of HBV in China. METHODS: There was a total of 1,904 patients with early BC who underwent mastectomy or breast-conserving surgery enrolled in our study. HBV infection on overall survival (OS) and hepatic metastasis-free survival (HMFS) was the main research indicator for this study. RESULTS: A total of 212 patients (11.1%) were identified with chronic HBV infection due to serum hepatitis B surface antigen (HBsAg) positive. HBsAg-positive patients had inferior OS (84.9% vs. 90.4%, P=0.005) and HMFS (92.5% vs. 97.1%, P=0.016) at 5 years than HBsAg-negative patients. Chronic HBV infection was an independent predictor of poor OS in patients with BC [multivariate analysis; hazard ratio (HR), 1.52; P=0.038], but not for HMFS. Subgroup analysis showed that chronic HBV infection was an unfavorable independent prognostic factor for OS in patients with stage II/III BC (HR, 1.59; P=0.025). The 5-year OS and HMFS rates of HBsAg-positive patients were 81.9% and 90.5% for patients with stage II/III BC, while those rates of HBsAg-negative patients were 88.5% and 96.3%, respectively. In stage I patients, there was no significant difference in 5-year OS (95.8% vs. 97.1%; P=0.629) and HMFS (100.0% vs. 99.0%; P=0.447). CONCLUSIONS: In conclusion, chronic HBV infection predicts a worse prognosis in patients with stage II/III BC, but not stage I BC.