Abstract 909: Disparate access and outcomes of immunotherapy treatment in patients with head and neck cancer.

Abstract Introduction: Head and neck cancers (HNC) are often treated with surgery, radiation, and chemotherapy which can cause significant morbidity. Immune checkpoint inhibitors activate the immune system to target cancer cells and may reduce treatment-related complications. We examined clinical and sociodemographic factors associated with first-line immunotherapy receipt and timing, and assessed survival impacts in a hospital-based cohort. Methods: Adults with advanced stage (III-IV) HNC (n=414,380) from the National Cancer Database (2004-2022) were analyzed. Multivariable regression estimated differences in time to immunotherapy and adjusted odds ratios (aORs) for receipt, adjusting for age, sex, race, tumor site, insurance, Charlson-Deyo comorbidity (CDCC), income, and education. Overall survival was evaluated using Cox models comparing immunotherapy timing relative to surgery (immunotherapy only, neoadjuvant, or adjuvant) versus no immunotherapy, adjusting for the same covariates plus radiation and chemotherapy. A secondary model among immunotherapy recipients evaluated survival by sociodemographic factors. Results: The cohort was 74.2% male, mean age 62.5 years, 85.6% White; 4.7% had immunotherapy. Black patients (ß 11.06, 95% CI 5.12-16.99), females (ß 6.24, 95% CI 1.99-10.50), and tumors in the mouth/oral cavity (ß 10.95, 95% CI 6.42-15.49) or nasopharynx/nasal cavity/sinus (ß 13.96, 95% CI 5.75-22.18) had longer times to immunotherapy compared to oropharynx. Areas with higher low-education also had delays. Older age was associated with shorter delays; insurance and income showed no differences. Females (aOR 0.83, 95% CI 0.80-0.86) and tumors in the mouth/oral cavity (aOR 0.78, 95% CI 0.75-0.81), larynx/hypopharynx (aOR 0.73, 95% CI 0.70-0.77), and nasopharynx/nasal cavity/sinus (aOR 0.6, 95% CI 0.63-0.73) had lower odds of receipt than oropharynx. Higher comorbidity, Medicaid/Medicare, and higher income were associated with increased odds of receipt. Adjuvant immunotherapy improved survival (aHR 0.95, 95% CI 0.90-0.99), while immunotherapy alone (aHR 1.25, 95% CI 1.22-1.29) and neoadjuvant therapy (aHR 1.12, 95% CI 1.04-1.20) were linked to worse survival compared to no immunotherapy. Older age, Black race, non-oropharynx tumors, higher comorbidity burden, lower income, and residence in areas with lower educational attainment were each independently associated with higher mortality. Among immunotherapy recipients only, Black race (aHR 1.23, 95% CI 1.14-1.31) and increasing CDCC scores predicted worse survival, while private insurance was protective (aHR 0.64, 95% CI 0.57-0.72). Conclusion: Differential access to immunotherapy and survival outcomes in HNC disproportionately affects racial minorities and socioeconomically disadvantaged populations, underscoring multifactorial determinants of survival and the need for equitable cancer care interventions. Citation Format: Morgan C. Byrd, Tariq M. Omer, Alexandra Hunter, Rong Jiang, Aleksandr R. Bukatko, Oyomoare L. Osazuwa-Peters, Tammara L. Watts, Nosa Osazuwa-Peters. Disparate access and outcomes of immunotherapy treatment in patients with head and neck cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 909.