[Primary Melanocytic Lesions are diffuse or circumscribed, benign or malignant tumors arising from melanocytes of the leptomeninges. This group includes: (1) Diffuse Melanocytosis (diffuse melanosis) and Neurocutaneous Melanosis, (2) Melanocytoma, and (3) Malignant Melanoma, but intermediate or mixed cases may occur. (Adapted from WHO.) ( NCI )]
UMLS (NCI) C0349623