A choroid plexus metastasis of a prostatic adenocarcinoma mimicking a choroid plexus carcinoma: A case report

A multicystic intraventricular tumour of the right ventricular atrium was incidentally diagnosed on follow-up imaging of a 61-year-old man with a history of prostatic adenocarcinoma. Surgical resection of the lesion was performed after a one-year radio-clinical follow-up due to progressive expansion of the lesion size and a rising prostate specific antigen blood-level. Morphological features with papillary pattern on pathological examination were compatible with malignant adenocarcinoma or choroid plexus carcinoma. The immunoprofile was conclusive for an exceptional choroid plexus metastasis (CPM) of a prostatic adenocarcinoma. To our knowledge, this is the first report of a proven prostatic origin of a CPM.

Third ventricular schwannoma with hydrocephalus

Intraventricular schwannomas are rare, with only 20 cases reported in the literature to our knowledge, including two cases of schwannomas in the third ventricle. We report a 23-year-old man with a mass in the posterior portion of the third ventricle and obstructive hydrocephalus. The intraventricular mass was clearly visualized and removed by neuroendoscopic surgery, and endoscopic third ventriculostomy was simultaneously performed for the hydrocephalus. Histological and immunohistochemical assays of the surgical sample established a diagnosis of intraventricular schwannoma. The patient had a favourable outcome and no neurological deficits 1 year later. The schwannoma was distant from the choroid plexus, which supports the hypothesis that the schwannoma originated from ectopic neural crest cells that were displaced during embryogenesis.