A rare case report of epithelioid hemangioendothelioma involving both lungs and right atrium with multi-system involvement

Figures

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  Figure 1. MRI (cardiac plain + function + perfusion + delayed enhancement): (A,B,C,F,G) show multiple soft-tissue nodules/masses around both atria and apex, right atrial involvement, increased mediastinal/epicardial fat, and minimal pericardial fluid. Diffuse lung nodules/patches are visible. (D,E) indicate marked diffusion restriction of lesions on DWI.

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  Figure 2. Whole-body PET/CT scan results: (A–D) reveal multiple soft-tissue masses/nodules around bilateral atria, pericardium, and mediastinum with elevated metabolism; diffuse lung nodules of varying sizes with increased metabolism; enlarged adrenal nodules with hypermetabolism; and focal metabolic upticks in the right humerus and right third/seventh ribs. (E,F) show diffuse lung nodules of different sizes.

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  Figure 3. Histological features of the tumor. (A) Tumor cells arranged in nests with abundant eosinophilic cytoplasm (×100). (B) Intracytoplasmic vacuoles containing erythrocytes (arrows), indicating primitive vascular lumen formation. Tumor cells show low-grade atypia with scattered mitotic figures, filling alveolar spaces in a polypoid pattern while sparing the alveolar septa (×400).

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  Figure 4. Immunohistochemical findings of the tumor. Representative immunohistochemical staining images showing the immunophenotypic profile of the tumor cells. The tumor cells exhibited diffuse positivity for VIM, CD34, ERG, and FLI-1, while showing complete negativity for CK (pan-cytokeratin). The absence of CK expression effectively ruled out an epithelial neoplasm (carcinoma), while VIM positivity supported a mesenchymal origin. Importantly, the combined expression of endothelial markers—CD34, ERG, and FLI-1—was consistent with a vascular lineage and strongly supported the diagnosis of EHE (scale bars, 50 μm; original magnification ×200).