The First Case of Composite Hemangioendothelioma in The Heart.

Composite hemangioendothelioma (CHE) is an extremely rare vascular neoplasm that is characterized by an admixture of benign, low-grade malignant, and malignant vascular components. It is usually located superficially in the dermis and subcutis of the extremities, and other sites involved include the head and neck region, oral mucosa, and viscera of the kidney and spleen. CHE has a low-grade malignant potential because it is locally aggressive. Here, we report a case of CHE in the heart in a 46-year-old man, who presented with a palpable mass arising from his right ventricle. Echocardiogram imaging revealed a 13.3 × 14.2 mm mass with high-signal intensity. Excision was performed, and microscopic examination revealed a heterogeneous mixture of vascular components, consisting of spindle-cell hemangioma, retiform hemangioendothelioma, and epithelioid-like hemangioendothelioma areas. To our knowledge, this is the first report on the behavior of this distinctive vascular neoplasm occurring in the right ventricle. Due to the unclear biological behavior of CHE in the heart and the paucity of cases, no further therapy was undertaken despite the risk of local recurrence and distant metastasis. The result of a six-month follow-up after surgery was disease-free.