Composite hemangioendothelioma: report of 5 cases including one with associated Maffucci syndrome.

Composite hemangioendothelioma (HE) is a low-grade malignant vascular tumor showing varying combinations of benign, low-grade malignant, and malignant vascular components. The predominant histologic components are histologically identical to epithelioid HE and retiform HE. To our knowledge, there have been only 12 cases of composite HE reported in the English literature and its nature and biologic behavior remains unknown. In this study, the clinicopathologic and immunohistochemical features of 5 cases of composite HE including a case with associated Maffucci syndrome are described. The patients were 4 females and 1 male with a median age of 43.4 years (range, 22 to 75 y). All tumors occurred in the dermis and/or subcutis. The tumors arose in the foot or lower leg in 3 patients, in the jaw in 1 patient, and as multiple tumors in the left upper extremity in 1 patient. Two patients had congenital tumors, in the lower thigh and foot, and upper extremity, respectively. The lesions were usually of several years duration. The size of individual tumors ranged from 1.5 to 30 cm. The tumors were composed of a complex admixture of histologic components resembling various vascular lesions. The predominant components, present in all cases, resembled retiform HE and epithelioid HE. Angiosarcomalike areas were observed in 3 cases. Lymphangiomalike areas were found in 2 cases. Areas of spindle cell hemangioma, cavernous hemangioma, or arteriovenous malformation were identified in 1 case each. The 2 congenital cases, which exhibited multiple lesions, had angiosarcomalike components and an angiomatosislike growth pattern. One patient each was associated with Kasabach-Merritt or Maffucci syndrome. Immunohistochemically, all tumors showed expression of at least 2 endothelial markers (CD31, CD34, and/or factor VIII-related antigen). Of 4 cases with follow up (median duration, 8.6y), 1 tumor recurred locally. To date, none of the patients have developed metastases. There was no difference of biologic behavior among cases with various combinations of histology in this study and previously reported cases. We conclude that composite HE should continue to be regarded as a low-grade malignant vascular tumor (HE), with significant potential for local recurrence, but little if any potential for distant metastasis.