Neurocutaneous melanosis in an adult patient with intracranial primary malignant melanoma: case report and review of the literature.

•The neurocutaneous melanosis (NCM) is a rare congenital disease,We through a rare case of an adult patient suffering from Neurocutaneous melanosis with malignant melanoma combined with those reported in Chinese and English literature, a total of 30 cases are analyzed.To explore the clinical characteristics of neurocutaneous melanosis in adult patients can help improve the level of diagnosis and the treatment of this disease.•When the congenital giant nevus in the head, the neck, back and buttocks have a large number of congenital melanoma cell nevus, especially when the melanin cell “satellite nevi” appear, the development of malignant lesions of the risk are larger than those congenital melanoma is limited to the hand-foot or lack of “satellite nevi” of the patients.•The early high mortality rate of child NCM patients, that may result in a paucity of genetic studies for patients and their children. The adult NCM patients who have children provided data samples for the study. The patient we reported was born with congenital giant nevus, but the patient's parents and daughter are both healthy and have no obvious pigmented nevi.•Question: The intracranial lesion has the tendency of malignant change, In the absence of neurological symptom in NCM children with increasing age, if skin lesions become malignant, can we assume that the intracranial lesions remain benign?