Outdoor summer jobs double risk of skin Ca

People who worked at outdoor summer jobs as teenagers for three years or more had twice the risk of developing malignant melanoma later in life as those who did not, according to case-control study by New York University Medical Center.

The study identified six independent risk factors, each of which increased the risk of malignant melanoma between two-and threefold, said at the annual meeting of the American Academy of Dermatology.

Besides an outdoor summer job, the other five risk factors were history of blistering sunburns, red or blonde hair, freckling of the upper back, family history of melanoma, and a history of actinic keratoses.

The study involved 300 consecutive patients with malignant melanoma who were seen at clinic. They were compared with 302 age- and gender-matched controls seen for acne, psoriasis, eczema, or other reasons unrelated to pigmented lesions. The average age of the patients was about 50 years, with a range from 18 years to the mid-70s.

All patients for the presence of 43 potential risk factors. Only six emerged as independent risk factors in a multivariate analysis.

There was at least one potential risk factor that was conspicuous by its absence from that list: the study showed no increase in melanoma risk with increasing age. “The model tended to predict early on in life what was going to happen later in life.”

The presence of any one of the six risk factors increased a lifetime risk to 3 to 5 percent. The lifetime risk of melanoma in the US population is about 1.5 percent.

The presence of two or more of the risk factors increased the lifetime risk of melanoma 5-10 times over that of the general population. Those with three or more of the risk factors have 10-fold to 20-fold increase in the risk of melanoma.

“Want to come up with a model that focuses as effectively as possible on those at high risk.” Eventually, these are not models. Using surrogates. Using factors that are not really the cause. The cause is genetic susceptibility and exposure to UV . . . . believe that 5 or 10 years from now will have a genetic screen for melanoma.

This study carries an important message for primary care physicians. “There’s only 9,000 dermatologists [in the United States]. Only one-third of dermatologic disease is treated by dermatologists. That means two-thirds are going to [primary care physicians]. We want those melanomas to be detected early. So models like this may let the primary care physicians also focus on who they should focus their efforts on.”