Causes of death and patterns of metastatic disease at the end of life for patients with advanced melanoma in the immunotherapy era

Despite remarkable advances in immunotherapy, melanoma remains a significant cause of cancer mortality. Many factors concerning melanoma mortality are poorly understood, posing an obstacle to optimal care. We conducted a retrospective observational cohort study of 183 patients with metastatic melanoma who died following immunotherapy treatment to investigate sites of metastases at death, settings of death, and mechanisms of death. The median time from metastatic diagnosis to death was 16.1 months (range 0.3-135.1 months). Most patients experienced hospitalization within 3 months before death (80.3%), with 31.7% dying while hospitalized, 31.2% while in inpatient hospice, and 29.4% while in home hospice. The most common sites of metastases at death were distant lymph nodes (62.8%), lung (57.9%), liver (50.8%), brain (38.8%), and bone (37.7%). The most common causes of death were progressive failure to thrive (57.5%), respiratory failure (22.4%), and infection (21.8%); the vast majority (87.9%) of patients died from melanoma-specific causes. Overall, 10.9% of patients in our cohort had survival >5 years after metastatic diagnosis, and 76.2% of long-term survivors died due to melanoma. This study describes factors associated with melanoma mortality, highlighting an ongoing need for therapeutic advancements.