Incidence and survival for oropharynx and non-oropharynx head and neck cancers among veterans living with HIV

Background: People living with HIV/AIDS (PLWH) have an excess risk for head and neck squamous cell carcinoma (HNSCC) compared to the general U.S. population, but little is known about HIV-specific risk factors associated with the incidence and outcomes HNSCC. We aim to identify clinical and HIV-specific risk factors associated with oropharyngeal and non-oropharyngeal HNSCC incidence and outcomes separately. Methods: We constructed a retrospective cohort study of 45,052 PLWH aged 18 or above from the national Veteran Affairs (VA) Corporate Data from 1999 to 2015. We extracted demographic data and risk factor information, including history of alcohol abuse, smoking, CD4 count (cells/μl), and percent of follow-up time with undetectable HIV viral load as time-updated variables. We calculated the age-standardized incidence rates of oropharyngeal and non-oropharyngeal HNSCC and estimated adjusted hazard ratios (HR). We also examined overall survival using Kaplan–Meier curves and adjusted HR. Results: The standardized incidence rate of oropharyngeal and non-oropharyngeal HNSCC in this veteran cohort of PLWH is 23.0 (95% confidence intervals (CIs): 17.1-28.9) and 55.4 (95% CI: 46.5-64.3) per 100,000 person-years, respectively. Nadir CD4 count ≤200 was associated with an increased risk of non-oropharyngeal HNSCC (HR: 1.78; 95% CI: 1.31-2.30 vs >200). Five-year overall survival of OPSCC (37.0%) was significantly lower than non-oropharyngeal HNSCC (49.1%). Conclusions: PLWH who receive care in the VA had higher age-adjusted HNSCC incidence rates than reported in the general population, suggesting that HIV and immunosuppression play a role. Additional studies should be conducted to study the interaction between HPV and HIV.