Increased prevalence of left-sided skin cancers

Background Previous research has shown an increase in photodamage and precancers on the left side of the face. Objective We sought to determine whether there is a higher frequency of skin cancer development on the left side of the body than the right. Methods The study was a retrospective review of patients with skin cancer referred to our Mohs micrographic surgery and cutaneous oncology unit in 2004. Results When including all types of skin cancers and both sexes, more cancers occurred on the left (52.6%) than the right (47.4%) ( P = .059), with a stronger trend in men ( P = .042). There were significantly more malignant melanoma in situ on the left (31/42, 74%) than the right (11/42, 26%) ( P = .002). Limitations Population was comprised of patients referred to an academic medical center and often for Mohs micrographic surgery. Conclusions There were significantly more skin cancers on the left than the right side in men. This discrepancy was even more profound in malignant melanoma in situ.