====== Primary meningeal melanomatosis ======

Meningeal [[melanomatosis]] is an extra-axial well-encapsulated malignant tumor with diffuse meningeal growth and dark coloration (due to high [[melanin]] contents), while [[meningeal melanocytoma]] is the focalized benign variant. [[Melanocytic tumor]]s may be secondary to [[melanoma]] or be histologically benign, however, their diffuse nature makes them impossible to cure. [[Melanocytosis]] is a diffuse tumor that can form solitary extra-axial tumors, which invades the parenchyma and presents signs of malignancy with increased [[mitosis]] and [[Ki67]], observed in 1 to 6% of immunopathological exams. [[Melanoma]] of the [[leptomeninge]]s, presents signs of malignancy with anaplastic cells, which cluster in fascicles of [[melanin]] in the cytoplasm, with more than 3 atypical mitoses per field and Ki67 presenting in more than 6% of the immunopathological fields analyzed
((Padilla-Vázquez F, Escobar-de la Garma VH, Ayala-Arcipreste A, Mendizábal-Guerra R, Cuesta-Mejía T. Melanocitoma y melanomatosis meníngea, lesiones similares pero diferentes [Melanocytoma and meningeal melanocytosis, similar but different lesions]. Cir Cir. 2017 May-Jun;85(3):273-278. Spanish. doi: 10.1016/j.circir.2016.11.006. Epub 2017 Jan 23. PMID: 28126183.)).

===== Treatment =====
[[Dacarbazine]] (16–20% efficacy) combined with [[radiotherapy]] and [[chemotherapy]] has recently proven to be the most effective treatment for [[melanomatosis]].


===== Case reports =====

A case of a patient with long-term meningeal melanomatosis, with progressive neurologic deficit and characteristic radiologic features
((Padilla-Vázquez F, Escobar-de la Garma VH, Ayala-Arcipreste A, Mendizábal-Guerra R, Cuesta-Mejía T. Melanocitoma y melanomatosis meníngea, lesiones similares pero diferentes [Melanocytoma and meningeal melanocytosis, similar but different lesions]. Cir Cir. 2017 May-Jun;85(3):273-278. Spanish. doi: 10.1016/j.circir.2016.11.006. Epub 2017 Jan 23. PMID: 28126183.)).