Imaging features of pediatric angiosarcomas: clinical, pathologic, and radiological review.

Background: Angiosarcomas are rare malignant vascular tumors and there is scarcity of data on their imaging features.

Objective: To review and illustrate the imaging, clinical, and pathologic features of angiosarcoma in children.

Materials and methods: A list of pathologically proven angiosarcoma seen between Nov 1992 and Jan 2023 was obtained from a pathology database and picture archiving and communication system. Those with pre-treatment imaging available on our PACS were included in the study. Imaging studies were reviewed by two readers in consensus.

Results: A total of six children (two males and four females; median age of 8.8 years; range 2.9 years to 15.5 years) had angiosarcoma during the study period. Organ of origin included breast (n = 2), liver (n = 2), spleen (n = 1), and paranasal sinuses (n = 1). The patient with splenic angiosarcoma had Li-Fraumeni syndrome. Five patients had a single lesion while one had multifocal lesions. The tumors were large with a median diameter of 12.9 cm (range 2.7 cm to 24 cm). Most tumors were heterogeneous on T2-weighted imaging with hemorrhage and necrosis and showed heterogeneous enhancement. Three had well-defined borders and three had infiltrative borders. None of the tumors showed calcifications. Two tumors in the liver showed gradual non-centripetal progressive diffuse enhancement on dynamic imaging. One patient had metastases at presentation and four patients subsequently developed metastases on follow-up. Five patients underwent surgical resection and chemotherapy; one patient with a liver lesion underwent arterial embolization followed by liver transplant. Three patients died at the last follow-up.

Conclusion: The imaging features of angiosarcomas are nonspecific, but the tumors are large heterogeneously enhancing masses with hemorrhage and necrosis. Hepatic angiosarcomas may show non-centripetal progressive and heterogeneous enhancement on dynamic imaging.