Effects of hepatitis B virus infection and antiviral therapy on the clinical prognosis of nasopharyngeal carcinoma

PURPOSE: To investigate the clinical characteristics of nasopharyngeal carcinoma (NPC) and a concomitant hepatitis B virus (HBV) infection, as well as the potential effects of HBV infection and antiviral therapy on prognosis. METHODS: We conducted a retrospective chart review of all NPC patients from December 2010 to December 2014. After collecting medical records and conducting follow‐ups on patients, a total of 876 eligible NPC patients were included. For each patient, medical records were reviewed. Factors predictive of outcome were compared using the log‐rank test and Cox regression analysis. RESULTS: Among the 876 participants, 106 (12.1%) patients were HBV‐infected patients. The hepatitis B surface antigen‐positive [HBsAg(+)] group had a lower CD(4+) T cell count than the HBsAg(−) group (P = .048). Among patients with stage I/II NPC, 5‐year overall survival (OS), disease‐free survival (DFS), relapse‐free survival, and distant metastasis‐free survival (DMFS) of the HBsAg(+) group were 82.5%, 70.7%, 87.7%, and 76.6%, respectively, whereas those of the HBsAg(−) group were 91.4%, 86.0%, 93.8%, and 92.1%, respectively. Statistically significant differences in OS, DFS, and DMFS existed between both groups (P = .017, .018, and .004, respectively). The multivariate analysis indicated that HBsAg status and N stage are independent risk factors affecting OS, DFS, and DMFS of NPC patients. A statistically significant difference in 5‐year DMFS existed between the antivirus (90.0%) and no‐antivirus groups (70.0%) (P = .043). CONCLUSIONS: Hepatitis B virus infection is an independent risk factor for early stage NPC, which may be associated with its reduced immune functions compared to the HBsAg(−) group. Anti‐HBV treatment may improve the prognosis of HBV‐infected NPC patients.