혈관종/혈관 기형 에서 발생한 혈관 육종

초록

Malignant vascular tumor spontaneously arising in a benign hemangioma is exceptionally rare. There are only rare case reports in the literature of angiosarcoma spontaneously arising in a hemangioma/vascular malformation. A new case of angiosarcoma arising in a hemangioma/vascular malformation is described. An 18-year-old female was admitted to our hospital because of a 2-month history of an enlarging palpable mass in left axillary area. Grossly, the tumor was relatively circumscribed, nodular, firm, and soft and measured 6.0x4.5x4.0cm. The cut surface revealed whitish gray solid area and dark red to tan cystic area containing necrotic material. Histologically, the tumor was poorly circumscribed and showed infiltrative border. Extensive hemorrhage and multifocal necrosis were present. The most striking features at low power examination were the presence of diffuse and infiltrative pattern and the variability in appearance from area to area. The tumor revealed haphazardly intermixed benign and malignant vascular components. The benign components showed features of an arteriovenous malformation, capillary hemangioma and cavernous hemangioma. Malignant component showed retiform hemangioendothelioma and angiosarcoma. Angiosarcoma showed mixed epithelioid and spindle shaped cytomorphology and moderate differentiation. An imperceptible transition between the two components was noted. The stroma showed fibrofatty tissue and moderate chronic inflammatory cell infiltrate, composed of predominantly lymphocytes with occasional lymphoid follicles.