Impact of HIV infection on clinical outcomes among people diagnosed with head and neck cancer.

Abstract

e18080 Background: Incidence of non-AIDS-defining cancers, including head and neck cancer (HNC), is rising among people with HIV (PWH) in the combination antiretroviral therapy (cART) era. The following study compares demographics, clinical outcomes, and the tumor microenvironment of HIV+ and Uninfected HNC patients at a single institution. Methods: Yale Tumor Registry query identified 3,356 HNC patients from 2002 to 2018 for analysis, including 50 PWH. In addition, quantitative immunofluorescence (QIF) was performed on tumor tissue from 22 PWH and 75 matched Uninfected patients. HPV status was based on p16 staining done universally among oropharyngeal squamous cell carcinomas (OPSCC) after 2010. Results: PWH were younger at cancer presentation compared to Uninfected patients (55.5 vs. 62.0, p < 0.001), with differences in race/ethnicity and insurance status (p < 0.001 for both). Biologic sex, tobacco use, alcohol consumption, anatomic site, stage at presentation, stage-specific treatment, and time to initiation of treatment were comparable between HIV+ and Uninfected cohorts. 89% of the PWH were on cART, with 79% achieving viral loads ≤200 copies/mL and a median CD4 count of 341 cells/mm³. Median survival among PWH was 39.1 months, compared to 100.8 months among Uninfected patients (p < 0.001). In a multivariate (MV) analysis that included age, sex, race/ethnicity, tobacco use, anatomic site, stage, time to treatment initiation and insurance status, HIV was an independent predictor of poor outcome (HR 1.88 with 95% CI: 1.25-2.81). Difference in survival was noted particularly in early stage (stages 0, I, II) cancer, with a median survival of 73.8 months in PWH compared to 141.9 months in Uninfected patients (p = 0.001). Survival was comparable among late stage (stages III, IV) HNC patients. Among PWH, increased HIV viral load was associated with poor outcome in a MV analysis (p = 0.03). Among HPV-associated OPSCC, PWH had decreased survival compared to Uninfected patients (p < 0.001). In our study of the tumor microenvironment by QIF, tumors of PWH had lower tumoral CD8 T cell infiltration (p = 0.04) and lower PD-L1 expression in tumor, stroma, and combined compartments (CPS) (p = 0.01, p = 0.03, and p = 0.01, respectively) compared to Uninfected patients. Conclusions: In our single institution study, HNC patients living with HIV experienced decreased overall survival, with HIV serving as an independent predictor of poor outcome in a multivariate analysis which included insurance status and treatment approaches. Difference in outcome was significant among early stage tumors and among HPV+ OPSCC. CD8 T cell infiltration and PD-L1 expression, both associated with improved outcomes in the general population, are decreased within the TME of PWH. Our data suggest that HIV-associated HNC is associated with poorer outcomes and highlight differences in tumor biology that require further detailed characterization in large cohorts.