Cranial computed tomography of malignant melanoma.

Two hundred seventy-five cranial computed tomography (CT) scans performed on 179 patients with malignant melanoma were reviewed. Of the 101 patients with confirmed cerebral metastases, CT demonstrated lesions in 93. In 72% of these, areas of increased attenuation were present in the precontrast scan. These lesions also enhanced after contrast infusion. There was a direct correlation between the extent of bleeding in the neoplasm and the density of the metastasis, at least 20% red blood cells per high power field were consistently present within lesions of increased attenuation. Cerebral metastases were occasionally associated with subdural or intracranial hemorrhage. Meningeal melanomatosis was recognized by CT only when associated with adjacent parenchymal metastases. In nine (11%) of 74 patients without clinical evidence of brain involvement, CT revealed cerebral metastases; this suggests that a staging CT scan might be useful on patients with diffuse or advanced local extracranial disease prior to definitive therapy.