Meningeal melanocytosis is a benign form of primary melanocytic tumour of the CNS that represents proliferation of melanocytic cells within the subarachnoid space 1. When associated with cutaneous melanocytic lesions, the conditions is known as neurocutaneous syndrome 3.
The melanocytic cells found in the subarachnoid space are believed to arise from leptomeningeal melanocytes of neural crest origin 1. Sometimes meningeal melanocytosis can extend to involve the perivascular spaces, importantly without direct invasion into the brain 1. The cells appear bland without atypia, necrosis or significant mitotic activity. If these features are found then a diagnosis of meningeal melanomatosis should be made 1.
- 1. Louis DN, Ohgaki H, Wiestler OD et-al. The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol. 2007;114 (2): 97-109. Acta Neuropathol. (full text) - doi:10.1007/s00401-007-0243-4 - Free text at pubmed - Pubmed citation
- 2. Painter TJ, Chaljub G, Sethi R, Singh H, Gelman B. Intracranial and intraspinal meningeal melanocytosis. AJNR. American journal of neuroradiology. 21 (7): 1349-53. Pubmed
- 3. Seth Love, David Louis, David W Ellison. Greenfield's Neuropathology, 2-Volume Set, Eighth Edition. ISBN: 9780340906811