[Cerebrospinal fluid in the diagnosis of cerebro-meningeal metastasis from malignant melanoma arising from giant congenital melanocytic nevus: case report].

We describe the case of a 28-year-old man with a giant congenital melanocytic nevus (GCMN) with malignant transformation to melanoma and metastasis on the central nervous system (CNS). We also make a summary of the pathological features from both lesions (GCMN and Melanoma), the occurrence of malignancy of GCMN, the organs more frequently involved with metastatic melanoma--with emphasis to involvement of CNS--just as the factors that cause malignant transformation of GCMN; the methods to diagnose metastases in CNS--emphasizing the importance of cerebrospinal fluid--and some therapeutical modalities for the metastatic melanoma in CNS.