Sex-related location of head and neck melanoma strongly argues for a major role of sun exposure in cars and photoprotection by hair.

Head and neck melanomas (HNMs) are frequent and have a poorer prognosis than melanomas at other sites. Photoprotection in these locations is difficult. In this population-based study of 279 HNMs diagnosed in a French region between 2004 and 2009, major differences were found between genders. A clearcut, sex-related distribution was found between a "peripheral" area (scalp, forehead, temples, ears, and neck) and a "central" one (other parts of the face), with 56.7% of HNMs being located in the peripheral area in men and 79.3% in the central area in women (P<0.0001). Moreover, HNMs located in the peripheral area occurred on the left side in 57.6% of men and on the right side in 73.1% of women (P=0.009). Peripheral HNMs differed from central HNMs by a higher proportion of invasive tumors, nodular or superficial spreading melanomas, and a lower proportion of lentigo maligna melanomas (LMMs). We hypothesized that this differential distribution between men and women could be explained mostly by a major role of long-term photoprotection by hair and sun exposure in a car. Important public health messages could result from these observations, such as the role of hairstyles in melanoma prevention and the importance of reducing sun exposure in a car, particularly in professional drivers.