Primary Malignant Melanomatosis of Leptomeninges

Primary malignant leptomeningeal melanomatosis is uncommon. Cases of this condition have been reported singly or in series not exceeding three.1-10To date, 83 cases with adequate clinical documentation have been studied at necropsy. Excluded from this count are eight cases of melanoblastic hyperplasia of leptomeninges and an atypical juvenile case deemed a medulloblastic neoplasm.11Included are 17 cases of leptomeningeal melanomatosis in childhood. Unlike that of the adult, however, childhood leptomeningeal melanomatosis is usually associated with extensive cutaneous nevi2; and unlike other melanoblastic lesions, leptomeningeal melanomatosis when found in children usually exhibits malignancy before puberty.2 In the first of two cases reported here, the leptomeningeal origin of malignant melanoblastic growth in an 80-year-old woman was verified at necropsy by microscopic examination of all tissues, including all pigmented skin lesions, which could have given rise to extracranial melanocarcinoma. So far as we are aware, this is