Diagnosis: Metastatic carcinomas
• Metastatic neoplasms can present as either single or multiple lesions causing raised intracranial pressure, focal neurologic deficits or epilepsy.
• Metastatic carcinomas are the most common central nervous system (CNS) neoplasms. The most common metastatic neoplasms are lung cancer, breast cancer, and melanoma. Sometimes metastases to the CNS present clinically before any signs or symptoms of the primary carcinoma. Immunohistochemistry can help determine the organ of origin.
• The majority of brain metastases are located in the cerebral hemispheres, especially in arterial border zones and at the junction of cerebral cortex and white matter. Usually more than one lesion is present.
• Hemorrhage into the neoplasm is characteristic of malignant melanoma, choriocarcinomas, and metastatic renal cell carcinoma (RCC).
• Histologically, the neoplasm is usually well demarcated from adjacent brain parenchyma and usually shows features identical or similar to those of the primary carcinoma
