CT Features of Intracranial Metastases of Unknown Primaries

Intracranial metastases of central nervous system are relatively common in patients with systemic cancer. Computed tomography (CT) scans of 60 patients of intracranial metastatic disease of unknown primaries, at the time of surgery, were retrospectively analyzed. These patients primarily presented with neurological dysfunction. They were operated upon for various reasons and histopathological diagnosis was obtained. There were 39 male and 21 female patients, with age range of 18 to 74 years. The common clinical symptoms were raised intracranial pressure without lateralization, acute onset hemiplegia and seizures. Multiple cranial nerve palsies were observed in 4 patients. Histopathologically the intracranial lesions consisted of metastatic adenocarcinoma (32 cases) or metastatic squamous cell carcinoma (28 cases). Among cases of adenocarcinoma, CT revealed solitary lesions in 17 and multiple lesions in 13 cases. Two had extraaxial deposition in the region of petrous apex. Out of squamous cell carcinomas, 17 lesions were solitary, while 10 were multiple and one had extraaxial deposition in the region of petrous apex. This study is unique as it consisted of CT features of intracranial metastases of unknown primary malignant disease elsewhere in the body.