A Rare Tumor that Mimicked Metastasis in a Patient with Breast Cancer: Epithelioid Hemangioendothelioma

Case of epithelioid hemangioendothelioma occurring in the postradiation setting for breast cancer

Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor, which is typically characterized by recurrent fusion genes. EHEs most commonly occur in the lung, liver, bone, and internal organs. EHE has rarely been reported to occur in the post-radiotherapeutic setting, the breast site or in association with breast cancer. The differential diagnosis for radiation-associated vascular lesions of the breast is classically limited to atypical vascular lesion and angiosarcoma and does not include EHE. We present the case of a woman with a history of breast cancer and post-surgical radiotherapy who went on to develop an EHE of the chest wall skin within 3 years of the completion of radiotherapy. Microscopically, the lesion was infiltrative and composed of anastomosing nests of epithelioid-to-spindled cells with eosinophilic and vacuolated cytoplasm. By immunohistochemistry, the cells were positive for ERG, D2-40, and CD31. The diagnosis was confirmed by identification of a characteristic WWTR1-CAMTA1 fusion gene using RNA sequencing. This case expands our understanding of radiation-associated tumors.

Imaging characteristics and prognostic values of hepatic epithelioid hemangioendothelioma on 18F-FDG PET/CT

Hepatic epithelioid hemangioendothelioma (HEHE) is a low-to-intermediate-grade malignant mesenchymal tumor. The diagnostic and prognostic values of 2-[18F] fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) to patients with HEHE have not been fully validated. Patient survival outcomes (including overall survival [OS] and progression-free survival [PFS]), lesions characteristics and semi-quantitative parameters, in terms of maximum standardized uptake value (SUV_max), peak SUV (SUV_peak), total lesion glycolysis (TLG) and metabolic tumor volume (MTV) on ¹⁸F-FDG PET/CT of 20 cases with HEHE were measured and analyzed. A total of 310 liver lesions were detected (excluding the diffuse-type lesions in 3 cases). Most lesions had higher SUV_max in delayed imaging than in early imaging (P = 0.013). Patients with multiple organs involved had higher death rate (P = 0.022), higher progression rate (P = 0.020), shorter OS (P = 0.011), larger lesion SUV_max (P = 0.048) and TLG (P = 0.033) than those with only liver involved. The area under curves (AUCs) from the receiver operating characteristic (ROC) curve analysis were 0.960, 0.949, 0.980 and 0.960 for SUV_max, SUV_peak, TLG and MTV, respectively, in predicting OS (P = 0.005, 0.008, 0.001 and 0.024, respectively). For predicting PFS, the AUCs were 0.791, 0.824, 0.857 and 0.813 (P = 0.036, 0.019, 0.010 and 0.024), respectively. Dual-time-point imaging may improve lesions detectability. Patients with multiple organ involved had worse prognosis. The higher SUV_max, SUV_peak, TLG and MTV of lesions, the worse prognosis of patients were found.