Prospective epidemiological study on cutaneous melanomas in the Vendee area

Introduction. The aim of this prospective study was to evaluate the incidence of melanoma in the Vendee area, coastal region of Eastern France, in 1997. Patients and methods. The 16 dermatologists in the Vendee area in 1997, grouped together in a local association, completed a sheet for each patient in whom a new melanoma had been diagnosed. During the same period, the hospital and private pathologists of the Vendee and surrounding areas reported their new cases of melanoma in patients residing at least six months of the year in the area. The data concerning the local population was supplied by the I NSEE (French national institute of economic and statistical information) and the CPAM (French health authority) supplied data on the practitioners' activity. The raw and standardized incidence was calculated by the epidemiologist and the statistician of the local Vendee Cancer registry. Results. One hundred fifteen new melanomas were diagnosed in Vendee in 1997, 97 by a dermatologist and 18 declared by a pathologist. There were 36 in situ and 79 invasive melanomas discovered in 68 women and 47 men (sex ratio: 1.46). The standardized rate of incidence according to the world model was of 98/100 000 for women and 7.8/100 000 for men. The frequency curve revealed two peaks: the first at 40-50 years of age and the second at 70-75. The mean Breslow index of the 79 invasive cancers was of 1.62 MM (range: 0.10-12.5 mm). The only statistically significant difference between the melanomas of the men and the women concerned the topography; there were more melanomas on the trunk in men and more melanomas on the lower limbs in the women. Forty-seven Dubreuilh melanomas were reported: 28 in situ and 19 invasive. Discussion. This prospective study determined the incidence of melanoma in Vendee in 1997. The figures have been compared with those of the Vendee cancer registry, founded in April 1997, and with those of various published studies. The comparison was difficult because of the difference in study methodology. The only figures obtained in the same conditions are those of the cancer registry and we compared them with those of the Haut-Rhin, area of Eastern France: the incidence was similar for the women in the two areas and greater for the men in the Haut-Rhin with regard to the invasive melanomas. Conversely, 44 in situ melanomas were declared in the Haut-Rhin over a 3 year period versus 37 in Vendee over a period of 1 year. The increase in the incidence of melanoma in Vendee in the years to come should permit the evaluation of the impact of the various preventive campaigns.