North-south differences in incidence and surveillance of cutaneous malignant melanoma in Italy.

In the Emilia-Romagna Region, as compared with the Sicily Region, a higher incidence of cutaneous malignant melanoma -especially of in situ and early invasive cutaneous malignant melanoma- coexisted with a higher level of clinical surveillance. The question of the direction of the cause-effect relationship between increased incidence and increased diagnostic scrutiny remains open.