Epidemiology of cutaneous melanoma in Sweden—Stage‐specific survival and rate of recurrence

Cutaneous malignant melanoma (CMM) incidence is increasing globally, making a thorough understanding of the disease and its outcomes essential for optimizing care even more urgent. In this population‐based, retrospective study, we investigated stage‐specific survival and recurrence/progression rates of CMM among patients diagnosed in Stockholm County Council during 2005–2012, before the wide introduction of targeted therapy. A total of 3,554 CMM patients from the Stockholm Melanoma Register were included. Information on comorbidities, progression, death, and treatments was obtained from nationwide registers and hospital electronic medical records. Unadjusted 5‐year survival varied from 91.4% for stage I to 24.6% for stage IV patients. Stage, age and gender were predictors of survival, with gender an independent predictor of survival for stages IA and IIA. 74.6% of patients remained recurrence/progression‐free during follow‐up, with 5‐year recurrence/progression‐free survival rates varying from 85.3% to 12.9% among stages I and IV patients, respectively. In addition to stage, male gender, and age, circulatory system comorbidities increased the risk for recurrence/progression. No statistically significant differences in progression rate for operated and non‐operated patients could be detected, possibly due to high rate (98.9%) of surgery. Our estimates of survival and recurrence rates are consistent with historical and global expectations and can serve as a baseline to gauge population‐level improvements with use of novel melanoma treatments. What's new? Recently approved targeted agents and DNA damage checkpoint inhibitors have led to improved survival in cutaneous metastatic melanoma (CMM). To accurately gauge the therapeutic effects of newly introduced therapies, it is essential to better understand patient outcomes under traditional care. Here, the authors used a novel methodology for automated extraction and linking of hospital electronic medical records to registry data to create a retrospective longitudinal study database with highly detailed patient‐level information and gain insights into survival and relapse/progression after CMM diagnosis. Increased stage and age at diagnosis and male gender were associated with increased probability of recurrence and death.