NCDB Analysis of Melanoma 2004–2015: Epidemiology and Outcomes by Subtype, Sociodemographic Factors Impacting Clinical Presentation, and Real-World Survival Benefit of Immunotherapy Approval

SIMPLE SUMMARY: Melanoma is clinicopathologically a heterogeneous disease with rising incidence. Metastatic disease is associated with poor outcomes, and immunotherapy was first approved in 2011 for its treatment. In our analysis of a large national database, we describe the epidemiology, clinical presentation, and survival outcomes of cutaneous, ocular, and mucosal melanoma in recent years. Metastatic cutaneous melanoma had better survival than both metastatic ocular and mucosal melanoma. We found higher odds of metastatic disease at diagnosis amongst African Americans compared to Caucasians. Additionally, for metastatic cases, we noted 25% lower mortality in those treated at an academic facility compared to community cancer programs and a 20% real-world survival benefit following approval of immunotherapy. This real-world survival benefit was definitely seen in Caucasians and those with cutaneous or mucosal melanoma. Further investigation is needed to confirm this benefit in African Americans and ocular melanoma. ABSTRACT: Background: The incidence of invasive melanoma is rising, and approval for the first immune checkpoint inhibitor (ICI) to treat metastatic melanoma occurred in 2011. We aim to describe the epidemiology and outcomes in recent years, sociodemographic factors associated with the presence of metastasis at diagnosis, and the real-world impact of ICI approval on survival based on melanoma subtype and race. Methods: This is a retrospective analysis of the National Cancer Database (NCDB) from the years 2004–2015. The primary outcome was the overall survival of metastatic melanoma by subtype. Secondary outcomes included sociodemographic factors associated with the presence of metastasis at diagnosis and the impact of treatment facility type and ICI approval on the survival of metastatic melanoma. Results: Of the 419,773 invasive melanoma cases, 93.80% were cutaneous, and 4.92% were metastatic at presentation. The odds of presenting with metastatic disease were higher in African Americans (AA) compared to Caucasians (OR 2.37; 95% CI 2.11–2.66, p < 0.001). Treatment of metastatic melanoma at an academic/research facility was associated with lower mortality versus community cancer programs (OR 0.75, 95 % CI 0.69–0.81, p-value < 0.001). Improvement in survival of metastatic melanoma was noted for Caucasians after the introduction of ICI (adjusted HR 0.80, 95% CI 0.78–0.83, p < 0.001); however, this was not statistically significant for AA (adjusted HR 0.80, 95% CI 0.62–1.02, p-value = 0.073) or ocular cases (HR 1.03, 95% CI 0.81–1.31, p-value = 0.797). Conclusion: Real-world data suggest a 20% improvement in survival of metastatic melanoma since the introduction of ICI. The disproportionately high odds of metastatic disease at presentation in AA patients with melanoma suggest the need for a better understanding of the disease and improvement in care delivery.