Lethal Melanomas: A Population-based Registry Study in Western Sweden from 1990 to 2014

The incidence rates of thin melanomas (≤1 mm Breslow thickness) have increased in many fair-skinned populations, prompting a need to better identify patients with thin melanomas who will eventually die from the disease. This study aimed to describe the clinicopathological characteristics of lethal melanomas in Western Sweden, with a focus on thin lesions. Population-based data on invasive melanomas diagnosed during the years 1990 to 2014 were extracted from the Swedish Melanoma Registry, and linked to the Swedish Cause of Death Registry. The age-standardized incidence (US population 2000) of thin melanomas increased from 9.1×10-5 (95% confidence interval (95% CI) 8.5-9.8) to 21.3×10-5 (95% CI 20.4-22.1) during the study period. Thin melanomas comprised 55.2% of the total and contributed to 13.5% of all melanoma deaths. Non-ulcerated melanomas 0.76-1 mm and ulcerated melanomas 0.26-1.0 mm showed a poorer survival compared with other thin melanomas.