Melanocytic neoplasms in neurofibromatosis type 1: a systematic review

Neurofibromatosis type 1 ( NF1 ) is commonly mutated in melanoma, yet the risk of melanoma in individuals with NF1 is incompletely understood. We performed a systematic review to investigate the risk and characteristics of melanoma and melanocytic nevi in NF1 individuals. PubMed was searched for articles describing NF1 individuals with melanoma, or melanocytic nevi. Those with cutaneous and ocular melanomas were compared to the general population using Surveillance, Epidemiology, and End Results data. Fifty-three articles describing 188 NF1 patients were included (melanoma n  = 82, melanocytic nevi n  = 93, melanocytic nevi, and melanoma n  = 13). Compared to the general population, NF1 patients with cutaneous melanomas had earlier melanoma diagnoses (49.1 vs. 58.6 years, P = 0.012), thicker tumors (3.7 vs. 1.2 mm, P = 0.006), and more frequent disease-specific deaths (27.3% vs. 8.6%, P = 0.005) with shorter survival (12.9 vs. 34.2 months, P = 0.011). Ocular melanomas made up 15.0% of all melanomas in NF1 patients versus 1.5% in the general population ( P < 0.001). In pooling all population-based studies describing melanoma in NF1 populations, NF1 individuals had 2.55 higher odds of having melanoma compared to the general population. A nevus spilus was commonly reported among NF1 individuals with nevi (44.8%, 39/87). Our findings suggest that NF1 individuals may have a higher risk for developing melanomas and tend to have thicker melanomas and worse survival compared to the general population, highlighting the importance of cutaneous and ophthalmologic surveillance in NF1 patients. Our review also supports the association between NF1 and nevus spilus.