Personalized surveillance in giant congenital melanocytic nevus, including the role of AI, histopathology and MC1R genotyping: A case report

Giant congenital melanocytic nevi (GCMN) are rare pigmented skin lesions present at birth that carry an increased risk of malignant melanoma and neurocutaneous melanosis. Early diagnosis and long‑term follow‑up care are essential for high‑risk patients. The combination of modern imaging techniques with genetic testing can enable a more comprehensive risk assessment. The present case describes a 55‑year‑old woman with a bathing‑trunk‑type GCMN and >30 additional nevi. The patient was monitored using total body mapping combined with artificial intelligence (AI)‑assisted dermoscopy (MoleAnalyzer Pro; FotoFinder Systems GmbH). Due to suspicious features, several lesions were surgically excised. Histopathology revealed a rare plexiform melanocytic schwannoma with low proliferative activity, showing immunopositivity for S100 protein and SOX10, with focal expression of Melan‑A (MART‑1). Germline testing by next‑generation sequencing identified two high‑risk melanocortin 1 receptor (MC1R) variants, p.Arg151Cys and p.Arg160Trp, in compound heterozygous state, both associated with melanoma susceptibility. No pathogenic variants were detected in NRAS or BRAF. The present case highlighted the integrative value of AI‑assisted dermoscopy, histopathology, and genetic profiling in the surveillance of patients with GCMN. Compound heterozygosity for MC1R high‑risk alleles may explain the extensive nevus burden and support intensified surveillance. Personalized follow‑up strategies guided by advanced imaging and genomics can improve early detection and prevention of melanoma.