Time Spent Driving an Automobile May Increase Skin Cancer Risk

Drivers who spend a significant amount of time in their cars might find themselves in the fast lane for developing future skin cancers, according to new research examining the incidence of left-sided skin cancers in patients and driving trends of adults seen at a Midwestern university dermatology clinic.

Speaking today at the 65th Annual Meeting of the American Academy of Dermatology, dermatologist Scott Fosko, MD, FAAD, professor and chairman of dermatology at Saint Louis University School of Medicine in St. Louis, Mo., discussed the possible relationships between left-sided skin cancers and driving.

“Since previous scientific findings have shown an association between one-sided exposure to ultraviolet light (UV) and an asymmetric facial distribution of sun damage, we would expect that skin cancers also would be more prevalent on the left side of the body in drivers who spend a significant amount of time in their cars,” said Dr. Fosko. “Our initial findings confirm that there is a correlation between more time spent driving and a higher incidence of left-sided skin cancers, especially on sun-exposed areas in men.”

A total of 898 patients (559 men and 339 women) with skin cancers occurring on either side of the body were included in a retrospective chart review conducted by Dr. Fosko and his team of researchers. Of the 53 percent of left-sided skin cancers that occurred in this group of patients, nearly two-thirds (64 percent) of left-sided skin cancers were found in men compared to approximately one-third (36 percent) in women. Dr. Fosko noted that his team also found a statistically significant number of left-sided skin cancers on sun-exposed areas (head, neck, arms and hands) in men, but not in women. This incidence directly correlates to the areas of the body most often exposed to UV radiation while driving.

Of the skin cancers that were reviewed, 608 were basal cell carcinomas, 178 were squamous cell carcinomas, 23 were invasive melanomas, 42 were in situ, or non-invasive, melanomas (25 malignant melanoma in situ and 17 lentigo maligna type malignant melanoma in situ), and 64 were miscellaneous cancers. While Dr. Fosko expected the number of basal cell carcinomas to be the highest type of skin cancers reported since they are the most common form and are associated with cumulative sun exposure, he was surprised by the number of non-invasive melanomas that occurred on the left side of the patients studied – 31 of the 42 non-invasive melanomas reported, which accounted for 74 percent.

“A subset of skin cancers found in the patients with in situ melanomas was lentigo maligna, which is a form of melanoma caused by cumulative sun exposure rather than the more common form of melanoma that occurs from intense, intermittent sun exposure,” noted Dr. Fosko. He observed that 70 percent of lentigo malignas occurred on the left side. “This finding supports our theory that drivers who regularly spend more time in the car over the course of several years are more likely to develop skin cancers on the left side of the body, particularly skin cancers like basal cell carcinoma and lentigo maligna that develop gradually over time.”