NEUROCUTANEOUS MELANOSIS - CLINICAL-FEATURES OF LARGE CONGENITAL MELANOCYTIC NEVI IN PATIENTS WITH MANIFEST CENTRAL-NERVOUS-SYSTEM MELANOSIS

Background: Patients with a large congenital melanocytic nevus (LCMN) may have associated leptomeningeal melanocytosis with or without centr al nervous system (CNS) melanomas. These patients are considered to ha ve neurocutaneous melanosis, a disorder that, when symptomatic or othe rwise manifest neurologically, carries a poor prognosis even in the ab sence of malignancy. Objective: Our purpose was to identify typical cl inical features in patients who have manifest CNS melanosis in associa tion with LCMN. Methods: The records of 117 patients with LCMN in the New York University Registry of LCMN and the reports of 172 cases of L CMN in the world Literature were included for features that might sign al a high risk for the development of manifest CNS involvement. Result s: Of the 289 patients with LCMN, 33 had manifest CNS melanosis. In al l 33 in whom symptomatic neurocutaneous melanosis was diagnosed, the L CMNs were present in a posterior axial location on the head, neck, bac k, and/or buttocks. ''Satellite'' nevi were known to be present in 31 of the 33 patients. Conclusion: Patients with LCMN in a posterior axia l location, especially when associated with ''satellite'' melanocytic nevi, are at greater risk for the development of manifest neurocutaneo us melanosis than patients with LCMN limited to the extremities or tho se who are lacking satellite nevi.