[Primary intracranial malignant melanoma associated with nevus of Ota: a case report]

A case of intracranial malignant melanoma associated with nevus of Ota is presented. A 77-year-old man was admitted to the department of neurosurgery, Fukui Medical School on June, 1985 because of developing disturbed consciousness. The physical examination on admission revealed pigmented lesion diagnostic of the nevus of Ota, anisocoria (R greater than L) and left hemiparesis. Computed tomographic (CT) scans demonstrated a high density mass in the left temporal lobe and the mass was homogenously enhanced after the injection of contrast agent. Left common carotid angiogram showed elevation of the middle cerebral artery and a slight vascular blush. Subtotal removal of the dark-colored tumor within the left temporal lobe and biopsy of the nevus were performed. Histopathological examination of the tumor revealed malignant melanoma and that of the skin biopsy was consistent with a nevus of Ota. Postoperatively DTIC, ACNU and vincristine were administered intravenously but the patient died three weeks after operation. At autopsy, widespread black pigmentation of the leptomeninges, communicating with the pigmented tumor in the left temporal lobe, covered the base of the brain and spinal cord. No melanoma was found outside the central nervous system. Primary intracranial melanoma associated with nevus of Ota is rare and only 6 cases have been reported in the literature. In this paper, primary intracranial melanoma associated with nevus of Ota and some other subjects are discussed.