Background: In 2005, the incidence of cutaneous melanoma ranked ninth among all cancers in France. Although it had been rising since 1980, its incidence began to slow after 2000. According to international studies, this change in incidence does not affect the different histological types of melanoma in the same way. Objectives: To describe, based on data from French cancer registries, the trend from 1998 to 2005 in the incidence of infiltrating cutaneous melanomas (invasive melanomas) according to anatomic-clinical type and Breslow index (i.e., tumor thickness). Method: Incidence cases of invasive cutaneous melanoma (ICM) were identified by 11 general metropolitan cancer registries in the Francim network. The cases corresponded to topographic codes C44 and histological codes 8720 to 8780 (behavior /3) of the International Classification of Diseases Applied to Oncology - 3rd edition (ICD-O-3). Incidence rates were standardized to the world population (direct standardization). The mean annual rate changes (MARCs, and their 95% confidence intervals, 95% CI) were calculated using an age-drift model. Results: 8,128 cases of MCI were diagnosed. There are significant differences in the distribution of cases between the two sexes according to lesion topography, anatomic-clinical form, and Breslow index. Overall, the incidence increased significantly for both sexes (AAR = +3.4% [95% CI: 1.5; 5.5] in men and AAR = +3.3% [95% CI: 1.6; 5.0] in women). This increase remains significant for superficial spreading melanoma (SSM) in both sexes and for Dubreuilh melanoma (DM) and "unclassified" melanomas (UM) in men. The incidence of melanomas with a Breslow depth of 1 mm increases significantly in men (TVAM = +6.6% [95% CI: 4.5–8.8]) and women (TVAM = +6.8% [95% CI: 4.9; 8.7]), whereas tumors of unspecified thickness decreased significantly (TVAM = -7.1% [95% CI: -12.2; -1.6] in men and TVAM = -13.1% [95% CI: -17.4; -8.6] in women). Conclusion: In women, the increase in the incidence of MCI is primarily linked to the increase in SSM-type melanomas. In men, the increase concerns not only SSMs but also MDs and MIs. The increase in the incidence of ICMs with a thickness of 1 mm is difficult to interpret because, at the same time, the incidence of ICMs of unspecified thickness is decreasing. These difficulties in interpretation should diminish as a result of better documentation of histoprognostic factors. (R.A.)