A Comparison of Melanoma Mortality among WWII Veterans of the Pacific and European Theaters

PURPOSE: To determine whether cutaneous melanoma is associated with past military service in tropical locations, as a test of the ‘critical periodʹ sunlight exposure hypothesis. METHODS: Mortality data from a longitudinal follow-up study of 5524 former prisoners of war (POW) and 3713 non-POW veteran controls, all white male veterans of World War II (WWII), were examined to determine whether death attributed to melanoma was associated with history of military service in Pacific or European theaters during WWII or with POW status. Deaths from colon cancer were used as a comparison outcome. RESULTS: During 50 years of follow-up, there were 18 deaths from melanoma and 83 deaths from colon cancer among the cohort. Melanoma mortality varied with theater of war and POW status, whereas colon cancer mortality was similar for all subgroups. Pacific War POWs were at the highest risk overall (odds ratio (OR), 3.35; 95% confidence interval (CI), 0.39–28.76), whereas veterans of the Pacific War had nearly the same risk of melanoma (OR, 1.04; 95% CI, 0.09–11.94) compared with veterans of the European War. European theater POWs had a higher risk than non-POW veterans (OR, 2.76; 95% CI, 0.31–24.81). None of these differences, however, were statistically significant. CONCLUSIONS: To the extent that POW status is associated with higher sun exposure, these data are consistent with the hypothesis that exposure to high levels of solar radiation in young adulthood is associated with a higher risk of melanoma mortality.