Incidence and mortality trends of primary cutaneous melanoma: A 50-year Rochester Epidemiologic Project study.

ABSTRACT

Background: National cancer reporting-based registry data, although robust, lacks granularity for incidence trends. Expert opinion remains conflicted regarding the possibility of melanoma overdiagnosis in the context of rising incidence without a corresponding rise in mortality. Objective: To characterize 10- and 50-year trends in melanoma incidence and mortality. Methods: Multicenter, population-based epidemiologic study utilizing the Rochester Epidemiology Project for Olmsted County, Minnesota residents diagnosed with melanoma from 01/01/1970 to 12/21/2020. Age- and sex-adjusted incidence and disease-specific mortality are calculated. Results: Two thousand three hundred ten primary cutaneous melanomas were identified. Current age- and sex-adjusted incidence rates increased 11.1-fold since 1970s (P < .001). Over the last decade, there is an overall 1.21-fold (P < .002) increase, with a 1.36-fold increase (P < .002) among females and no significant increase among males (1.09-fold increase, P < .329). Melanoma-specific mortality decreased from 26.7% in 1970s to 1.5% in 2010s, with a hazard ratio (HR) reduction of 0.73 (P < .001) per 5-year period. Increased mortality was associated with Breslow thickness (HR 1.35, P < .001), age at diagnosis (HR 1.13, P = .001) left anatomic site (HR 1.98, P = .016), and nodular histogenic subtype (HR 3.08, P < .001). Limitations: Retrospective nature and focused geographic investigation. Conclusion: Melanoma incidence has continued to increase over the past decade, most significantly in females aged 40+. Trend variations among age and sex cohorts suggests external factors beyond overdiagnosis may be responsible. Disease-specific mortality of melanoma continues to decrease over the last 50 years.