An extremely rare case of epithelioid hemangioendothelioma presumed metastasis to the pineal body.

Abstract

Background: Epithelioid hemangioendothelioma (EHE) is a rare malignant endothelial tumor of blood and lymph vessels composed of epithelioid cells within a distinctive myxohyaline stroma. Its predilection sites are soft tissues, bone, lung, and liver, and intracranial metastases are extremely rare. We describe a case of EHE in an elderly patient with pineal body metastasis.

Case description: An 84-year-old man presented to our hospital with disturbance of consciousness. Neuroimaging showed hydrocephalus and pineal tumor with hemorrhage on computed tomography and gadolinium enhancement on T1-weighted magnetic resonance imaging. Cerebral angiography showed no obvious tumor staining. ¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography demonstrated accumulations of FDG consistent with the pineal tumor and in the vessel wall and muscle throughout the body. Various tumor markers in the blood and cerebrospinal fluid were negative. Endoscopic biopsy was performed to confirm the diagnosis and to treat the hydrocephalus by endoscopic third ventriculostomy. Histological examination revealed large epithelioid perivascular cells with abundant pale eosinophilic cytoplasm and cytoplasmic vacuolation. Immunohistochemical studies showed positive results for CD34, CD31, cytokeratin AE1/AE3, and calmodulin binding transcription activator 1, and EHE was therefore diagnosed. Because of poor general condition and progressive tumor growth, radiotherapy was administered 7 days after surgery. At 21 days after surgery, endoscopy performed for progressive anemia revealed metastases in the stomach. The lesions continued to grow and the patient died 2 months after surgery.

Conclusion: We present an extremely rare case of EHE presumed metastasis presenting as an isolated pineal region tumor. If a tumor with hemorrhage is found in the pineal body in an elderly patient, EHE should be considered in the differential diagnosis, even if it is a single tumor lesion.