Melanoma prognosis has improved in the last 30 years as a consequence of earlier diagnosis. However, very thick melanomas (VTMs) are still frequently identified. Risk factors associated with advanced tumors have remained unclear. In this retrospective case study, Grange et al demonstrate that VTMs were more often diagnosed in general practice settings, and rates of immediate clinical recognition by dermatologists were lower for VTMs. Also, VTMs were less likely to follow the ABCD rules (asymmetry, border irregularity, color variegation, and diameter >6 mm), and the most significant risks were observed for men, the elderly, and patients living alone. These data suggest that prevention programs should focus on atypical/non–ABCD criteria tumors in men, the elderly, and patients living alone.