Familial melanoma: genetic, clinical, and dermoscopic insights and follow-up

Familial melanoma accounts for approximately 5-10% of all melanoma cases. It is characterized by an earlier age of onset. Multiple primary melanomas occur in up to a fifth of patients with a positive family history, compared to 5% in sporadic cases. Pathologically, familial melanomas tend to present at thinner Breslow depths and show a higher proportion of in situ lesions compared to their sporadic counterparts, with a predilection for the lower limbs. The genetic landscape of familial melanoma is heterogeneous. CDKN2A and CDK4 mutations act through UV-dependent and cell cycle disruption pathways, while BAP1, POT1, and TERT mutations are considered UV-independent. Beyond cutaneous melanoma, germline mutations confer an increased risk for additional malignancies, including pancreatic cancer, renal cell carcinoma, mesothelioma, and neural system tumors, necessitating multidisciplinary surveillance and genetic counseling for affected families. Dermoscopically, CDKN2A mutation carriers predominantly present with superficial spreading melanoma, displaying atypical pigment networks, irregular dots and globules, regression structures, and a blue-white veil. Co-occurrence of MC1R variants may produce more subtle, structureless presentations with a lower total dermoscopy score, posing additional diagnostic challenges. Sequential digital dermoscopy and total body photography remain the cornerstones of surveillance, with follow-up every 3-6 months recommended for mutation carriers. All patients should receive structured education on photoprotection, including the use of broad-spectrum SPF50+ sunscreen and sun avoidance measures.