Recent Trends in Cutaneous Melanoma Incidence Among Whites in the United States

Abstract

Background: It is not yet clear whether increasing melanoma incidence is real or whether recent incidence trends mainly reflect improved diagnosis. To address this question, we examined the most recent melanoma incidence patterns among the white population stratified by sex, age, tumor stage, and tumor thickness by use of data from the Surveillance, Epidemiology, and End Results Program. Methods: We examined log-transformed age-specific rates for melanoma by 5-year age groups and time periods by year of diagnosis and birth cohort. Melanoma trends were further examined among broader age groups (t test. Results: Melanoma incidence increased in females born since the 1960s. From 1974–1975 through 1988–1989, upward trends for the incidence of localized tumors and downward trends for the incidence of distant-stage tumors occurred in the age group under 40 years. In the more recent time period, 1990–1991 through 1996–1997, agespecific rates among females compared with males generally remained stable or declined more for distant-stage tumors and increased less for local-stage tumors. Thin tumors (P<.05 for all), except in men under age 40 years. In contrast, rates for thick tumors (≥4 mm) increased statistically significantly (P = .0003) only in males aged 60 years and older. Conclusion: Melanoma incidence may well continue to rise in the United States, at least until the majority of the current population in the middle-age groups becomes the oldest population. The recent trends may reflect increased sunlight exposure.