Factors influencing receipt and time to treatment of immunotherapy relative to chemotherapy in stage III and stage IV melanoma

Background: Immunotherapies have changed the landscape of late-stage melanoma; however, data evaluating timely access to immunotherapy are lacking.Methods: A retrospective cohort study utilizing the National Cancer Database was conducted. Stage III and IV melanoma cases diagnosed between 2011 and 2018 that received systemic treatment with either immunotherapy or chemotherapy were included. Chemotherapy included BRAF/MEK inhibitors. Multivariable logistic regression models were utilized to evaluate factors associated with the likelihood of receiving immunotherapy as primary systemic treatment relative to chemotherapy; additionally, Cox proportional hazards models were utilized to incorporate time from diagnosis to primary systemic therapy into the analysis.Results: The study population was comprised of 14,446 cases. The cohort included 12,053 (83.4%) immunotherapy and 2393 (16.6%) chemotherapy cases. In multivariable logistic regression analysis, factors significantly associated with immunotherapy receipt included population density, circle distance, year of diagnosis, Breslow thickness, and cancer stage. Immunotherapy timing was evaluated using multivariable Cox regression analysis. Minorities were less likely to receive timely immunotherapy than non-Hispanic Whites (HR 0.83, CI 0.74-0.93, p = 0.001). Patients at circle distances of 10-49 miles (HR 0.94, CI 0.89-0.99, p = 0.02) and >= 50 miles (HR 0.83, CI 0.77-0.90, p < 0.001) were less likely to receive timely immunotherapy.Conclusion: Patients traveling >= 10 miles and minorities have a decreased likelihood of receiving timely immunotherapy administration for primary systemic treatment. Future research is needed to identify what barriers and approaches can be leveraged to address these inequities.