Intracranial Metastases from Prostate Carcinoma: Classification, Management, and Prognostication

Background: Prostate carcinomas rarely metastasize to the central nervous system but, when they do, dural localizations are as common as and far more aggressive than intraparenchymal ones. Those metastases can be further classified according to their extension toward the subdural or extradural space and can frequently simulate other pathologic conditions including chronic subdural hematomas, abscess, and primary bone tumors. Beside the challenges of the preoperative differential diagnostic and complexity of surgical planning and operative excision, subdural metastases seem to carry a much poorer prognosis. Methods: A series of consecutive patients admitted during a 12-year period through our oncall pathway for subdural/extradural collections or intraparenchymal lesions found, on histologic analysis, to represent intracranial prostate cancer metastases was retrospectively reviewed. Results: A total of 19 patients were included, but only 3 were diagnosed with small cell prostate carcinoma, while the majority had a primary prostate adenocarcinoma. Metastases could be classified as pure subdural space lesions, dural-based lesions, extradural/bony lesions, and pure intraparenchymal lesions. All patients with subdural metastases and 3 out of 5 patients with dural-based lesions required an emergency intervention due to rapidly deteriorating neurologic status. The mean follow-up in our series was 37 months; only subdural localizations had a remarkably unfavorable outcome. Conclusions: Supported by our experience and the review of the literature, we suggest that a low threshold for contrast-enhanced computed tomography/magnetic resonance imaging is advisable in case of suspicious subdural collection, even in an emergency setting, for patients with previous medical history of prostate cancer.