Unusual behaviour of a pineal germinoma mimicking neurosarcoidosis and metastasising along the endoscopic route.

A previously healthy man underwent endoscopic biopsy for a suspected pineal germinoma. Histology and immunohistochemistry did not confirm the preoperative diagnosis, and neurosarcoidosis was hypothesised because of the presence of granulomatous reaction. The patient remained in good health for 3 years and was still asymptomatic when a control MRI showed metastasis implantation along the endoscopic route. A redobiopsy provided the diagnosis of germinoma, but was complicated by severe ventricular haemorrhage requiring emergency clot excision. Postoperative clinical conditions were so severe that the treatment of germinoma was postponed. Three months later, repeated MRI showed tumour progression. Chemotherapy promoted good tumour regression so that the treatment was completed by radiation therapy. The tumour completely disappeared on MRI, but the patient remained severely disabled because of the haemorrhage.