Racial and Socioeconomic Disparities in the Delivery of Immunotherapy for Metastatic Melanoma in the United States

Immunotherapy for metastatic melanoma has rapidly expanded, but racial and/or socioeconomic factors often impact the type of therapies delivered for cancer care. This study addressed a crucial public health priority by evaluating disparities in administration of immunotherapy for metastatic melanoma. The National Cancer Database was queried for newly diagnosed metastatic melanoma. Patients were dichotomized based on receipt of immunotherapy based on National Cancer Database coding. Multivariable logistic regression ascertained factors associated with immunotherapy delivery. Subgroup analysis evaluated the interaction between race, insurance status, and income. Secondarily, Cox multivariate and propensity-matched Kaplan-Meier analyses assessed overall survival based on immunotherapy receipt. Of 15,941 patients meeting the selection criteria, 2448 (15.4%) received immunotherapy, and 13,493 (84.6%) did not. Temporal trends showed that utilization of immunotherapy was 8%-12% of patients between 2004 and 2010, with utilization increasing to 29.7% of patients in 2014. Immunotherapy was more likely administered to younger and healthier patients, at academic centers, and in the absence of chemotherapy and brain metastases (P<0.05 for all). African Americans, along with patients with Medicaid and lower incomes were less likely to receive immunotherapy (P<0.05 for all). As expected, immunotherapy was associated with improved overall survival (median 16.3 vs. 8.3 mo, P<0.001). Although immunotherapy for metastatic melanoma is markedly escalating, not all populations experience this rise equally. Because immunotherapy utilization is expected to amplify even further in the future, these public health and economic issues are essential to identify and address appropriately, and have implications on public health policy, pharmaceutical and insurance companies, and value-based oncology. Methods to address these inequalities are also discussed.