Leptomeningeal Metastatic Prostate Cancer Imitating a Subdural Hematoma.

Metastases to the dura and adjacent parenchyma occur in 1%-2% of patients with prostate cancer. Dural metastases manifest as subdural fluid collections and present as a chronic subdural hematoma. We present a patient with advanced prostate cancer who experienced a fall and a traumatic brain injury. Computer tomography (CT) of the brain revealed a bilateral subdural hematoma (SDH). During the follow-up examination, the patient's mental status declined, and a follow-up brain CT showed an expansion of the SDH. Brain MRI with contrast demonstrated dural lesions suspicious for metastasis to the dura. Histopathologic examination of the lesions confirmed metastatic prostate adenocarcinoma. While uncommon, leptomeningeal-dural metastatic lesions stemming from prostate adenocarcinoma should be suspected in patients with known prostate cancer who present with subdural collections. This is even more significant if the patient with prostatic adenocarcinoma has sustained a recent head injury and presents with a subdural hematoma on neuroimaging. Brain MRI provides more data towards the differential diagnosis of these lesions and should be an essential part of the diagnostic workup. Biopsy and histopathologic examination of these lesions are indicated in the diagnostic workup of these uncommon lesions.