Abstract

Neurocutaneous melanosis (NCM) is a congenital disorder characterised by large or multiple melanocytic naevi and pigment cell tumours of the leptomeninges. Malignant leptomeningeal melanoma occurs in over half of the cases and has a poor prognosis. This disorder stems from melanoblast abnormalities and NRAS gene mutations. Magnetic resonance imaging (MRI) cannot distinguish between benign and malignant cases. Positron emission tomography-computed tomography (PET-CT) may detect malignancies, whereas computed tomography (CT) has limited use. We report on a 34-month-old Sudanese female patient, diagnosed with neurocutaneous melanosis, meeting the diagnostic criteria through dermatological evaluation and brain MRI. Melanoma associated with NCM is infrequently documented, presenting significant diagnostic and therapeutic challenges that necessitate accurate diagnosis and treatment.

Key words: giant congenital melanocytic nevus, neurocutaneous melanosis, Sudanese girl.