The impact of chronic hepatitis C virus infection on survival in oropharyngeal cancer patients.

Abstract

e17556 Background: An association between Hepatitis C virus (HCV) infection and oropharyngeal cancers (OPCs) has been reported; however, the clinical significance of this epidemiological finding remains unknown. We therefore analyzed the oncologic outcomes of HCV-infected patients (pts) with OPCs. Methods: In this retrospective cohort study, all pts with OPCs seen at MD Anderson (1/2004-12/2015) were reviewed. HCV infection was defined as detectable HCV RNA in serum. Risk of 5-year (yr) overall survival (OS) and progression-free survival (PFS) was compared between HCV-infected (HCV+) and uninfected (HCV-) pts. OPCs that were positive for p16 by immunohistochemistry were considered HPV-related. Antiviral therapy (AVT) included either interferon (IFN)-based or IFN-free regimens. Multivariate cox proportional hazards model was used to identify independent predictors of mortality. Results: We studied 161 pts. Most of the pts were white (141; 88%), male (132; 82%) and had tumor stage 3 or 4 (147; 92%). The OPC involved tonsils (83; 52%), base of tongue (67; 42%) or soft palate (11; 7%). The median follow-up time after OPC diagnosis was 3 yrs (range: 1-13 yrs). HCV+ (n = 25) and HCV- pts (n = 136) were comparable in regards to smoking and alcohol status. In univariate analysis, HCV+ pts had more OPC progression after 1stline cancer treatment (48% vs 20.6% in HCV-, P = .0009) and were more likely to relapse (26% vs 5% in HCV-, P = .02). In multivariate analysis, HCV was associated with increased all-cause mortality [hazard ratio (HR): 2.15, 95% confidence intervals (CI): 1.08-6.85; P = .02] and risk of OPC progression [HR: 5.42, 95% CI: 2.64-11.14; P = .0008] independent of age and cirrhosis status. In HPV+ OPCs (n = 86), HCV + and HCV- pts did not have significant difference in mortality [HR: 2.03, 95% CI: 0.82-4.98; P = .12]. AVT was administered after OPC diagnosis in 8 of the 25 HCV+ pts (32%), with 6 of them receiving IFN-free AVT. HCV+ pts that received AVT had better 5 yr OS (median of 5.2 vs 2.3 yrs, P = .005) and PFS (median of 3.1 vs 0.7 yrs, P = .007) than the ones who did not. Conclusions: HCV seems to affect the oncologic outcomes of pts with OPCs and treating this infection might be beneficial. HCV screening and treatment should be considered in such pts.