Intra-Parenchymal Cerebellar Metastasis—A Rare Presentation of Castration-Resistant Prostate Cancer

Intracranial metastases from prostate carcinoma are uncommon and usually manifest as dural secondaries in the supratentorial compartment. We present an unusual case of intra-parenchymal posterior fossa prostatic metastasis in a 61-year-old gentleman and discuss the diagnostic and management challenges involved. A 61-year-old hypertensive, diabetic man presented with gait unsteadiness for 1-month duration and no other neurological deficits. He had previously undergone bilateral orchiectomy for prostate carcinoma with multiple osseous metastases. Magnetic resonance imaging showed a well-defined lobulated, intraventricular, peripherally enhancing lesion in the fourth ventricle with obstructive hydrocephalus. He underwent sub-occipital craniectomy and decompression, and histological examination was consistent with metastatic prostate adenocarcinoma. Although cerebellar secondaries are atypical, a suspicion of metastasis should be upheld in all patients with the history of prostate carcinoma, regardless of their location and radiological characteristics of the intracranial lesion.