Large congenital melanocytic nevi and neurocutaneous melanocytosis: One pediatric center's experience

Background Large congenital melanocytic nevi (LCMN) predispose to neurocutaneous melanocytosis (NCM), which is associated with significant morbidity and mortality. Objective To identify risk factors for NCM in patients with LCMN and suggest guidelines for their management. Methods Medical records of patients with LCMN were reviewed at Sainte-Justine Hospital between 1980 and 2006. Presence of multiple satellite nevi and posterior midline location were evaluated as risk factors for NCM using chi-square test. Magnetic resonance imaging scans were reviewed by a neuroradiologist. Results Twenty-six of 52 patients underwent radiologic investigation. Six of 26 (23%) had NCM. Patients with this condition are more likely to have multiple satellite nevi (100% vs 50%, P = .03) and have a trend to posterior midline location of their LCMN (100% vs 60%, P = .08). Patients with NCM are more likely to have both multiple satellite nevi and posterior midline location (100% vs 25%, P = .002). Radiologic findings are also presented. Limitations This was a retrospective case series with imprecise chart data in 38% of cases. Conclusion The presence of multiple satellite nevi alone or with associated posterior midline location of LCMN is associated with a higher risk of NCM. We recommend magnetic resonance imaging testing before 4 months of age in patients with these features.