Gender differences, UV exposure, and risk of lentigo maligna in a nationwide healthcare population cohort study.

BACKGROUND: Our understanding of the relationship between ultraviolet radiation exposure and lentigo maligna (LM) has been largely derived from epidemiologic/clinical studies based on invasive melanoma. Recent studies have shown gender differences in melanocytic tumors incidence.

OBJECTIVE: To examine the association of UV light with LM by gender remains unclear.

METHODS: Two prospective cohort study (Nurses' Health Study [1980-2012]) and (Health-Professionals Follow-up Study [1986-2010]) were analyzed. All participants with LM or MIS, non-LM type were included in analysis. UV index at birth, age 15, and age 30 were calculated by gender. Lifetime UV flux was calculated. Hazard ratios (HRs) were calculated.

RESULTS: 110,485 women from NHS and 41,015 men from HPFS were examined. 281 LM and 776 melanoma in situ (MIS), non-LM cases were reported. Risk of LM increased with increasing UV flux exposure in multivariate-adjusted models for men (p for trend=0.04), but not for women (p for trend=0.91).

CONCLUSIONS: UV flux may be associated with LM in men but not in women. This article is protected by copyright. All rights reserved.