Radiation-Induced Angiosarcoma of the Breast: A Case Report with FDG PET/CT Imaging Findings

ABSTRACT
Introduction: Breast angiosarcoma is a rare tumor arising from the vascular endothelium, accounting for approximately 1% of all soft tissue breast tumors and carrying poor prognosis. It manifests in two distinct types: Primary breast angiosarcoma (PBAS) and secondary breast angiosarcoma (SBAS). PBAS typically affects young women without a history of breast cancer or radiotherapy, often originating from the breast parenchyma with occasionally skin involvement presenting as a rapidly growing, usually painless, palpable mass. In contrast, SBAS occurs in older women, originates from the breast dermis, occasionally involves the parenchyma, displays multifocality, and presents characteristic features such as skin discoloration and swelling. There is a lack of cases in the current literature reporting radiation-associated angiosarcoma of the breast with imaging findings using Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET-CT ). This case report details the development of radiation-associated angiosarcoma in a 55-year-old woman who underwent breast-conserving surgery and subsequent radiotherapy for left breast cancer.
Case: The patient developed radiation-associated angiosarcoma 48 months after radiotherapy, with non-specific mammographic and ultrasound features. FDG PET-CT revealed increased FDG uptake in the breast skin and nodular lesions. Pathological examination of the nodules with increased FDG uptake confirmed radiation-induced breast angiosarcoma. The patient underwent a total mastectomy for treatment.
Conclusion: In patients with a history of breast-conserving surgery and radiotherapy, presenting symptoms during follow-up should prompt consideration of radiation-associated angiosarcoma. Early diagnosis is crucial, and FDG PET-CT can be beneficial for local visualization and distant organ metastasis screening.
Keywords: Radiation-associated angiosarcoma, breast-conserving surgery, radiotherapy, FDG PET-CT