Neurocutaneous melanocytosis presenting in a teenager: A case report and review of the literature.

Neuro cutaneous melanocytosis (NCM) is a non-familial, congenital disorder characterized by multiple congenital nevi and brain or leptomeningeal abnormal melanin deposits. Here, we present an adult onset NCM. A 17-year-old boy presented with headache and double vision for 1 month. Magnetic resonance imaging of the brain showed hydrocephalus and abnormal meningeal hyper intensities in supra and infratentorial regions predominantly in the posterior fossa. Para medullary region showed an 11×10 mm nodular contrast enhancing nodule. Resection of an intramedullary central nervous system lesion revealed melanoma while skin biopsy was benign melanocytic nevus. As per Kadonaga and Frieden criteria, a diagnosis of NCM was made. Planned for craniospinal irradiation by three-dimensional conformal radiotherapy with a dose of 36 Gy, in 18 fractions (2 Gy/fraction and 5 days in a week) along with steroids however patient progressed and developed quadriplegia with intradural metastasis.