The incidence and survival of melanoma and nonmelanoma skin cancer in patients with vitiligo: a nationwide population-based matched cohort study in Korea.

Background While studies report a lower incidence of skin cancer in white patients with vitiligo compared with controls, the skin cancer incidence in Asian patients with vitiligo is unknown. Objectives To quantify the incidence of melanoma and nonmelanoma skin cancer (NMSC) in Korean patients with vitiligo and compare it with matched nonvitiligo controls. Methods A retrospective matched cohort study was performed with 131 245 incident vitiligo cases and 2 624 900 age- and sex-matched (1 : 20) controls at index date, who were selected from the Korean National Health Insurance database between January 2005 and December 2017. Stratified Cox proportional hazards regression (stratified by sex, birth year and index year) was used to calculate the hazard ratio (HR) of skin cancer in patients with vitiligo. Results Patients with vitiligo were followed up for a mean duration of 6 center dot 34 years compared with a follow-up period of 6 center dot 27 years for matched controls. Ultraviolet (UV) treatment-adjusted HR for melanoma in patients with vitiligo was 3 center dot 32 [95% confidence interval (CI) 2 center dot 29-4 center dot 81] and 1 center dot 29 (95% CI 1 center dot 06-1 center dot 56) for NMSC. The HRs for melanoma and NMSC in the vitiligo population without a history of UV treatment were 3 center dot 37 (95% CI 2 center dot 32-4 center dot 90) and 1 center dot 35 (95% CI 1 center dot 11-1 center dot 64), respectively. Conclusions In contrast to white patients with vitiligo, the risk of skin cancer was increased in the Korean vitiligo population. However, it is noteworthy that the skin cancer incidence in Korean patients with vitiligo was lower than that of their white counterparts. Owing to possible ethnic differences in the susceptibility to skin cancer, skin cancer surveillance in the vitiligo population may be adjusted for race. What's already known about this topic? Prior studies have reported a lower incidence of melanoma and nonmelanoma skin cancer (NMSC) in white patients with vitiligo compared with nonvitiligo controls. The skin cancer incidence in Asian patients with vitiligo is unknown. What does this study add? In contrast to white patients, the risk of both melanoma and NMSC was increased in Korean patients with vitiligo compared with controls. Owing to possible ethnic differences in susceptibility to skin cancer, skin cancer surveillance in the vitiligo population should be adjusted for race.