case_images: PMC10864153_01
case_images: Multicentric epithelioid angiosarcoma of bone involving lower extremities in a 61-year-old male.. A. Plain radiograph of both femurs and lower extremity CT of the left thigh. Anteroposterior view shows multiple ill-defined osteolytic lesions in both centric and eccentric ways. Pathologic fracture is combined at the right femur (arrow). Note the cortical destruction with minimal periosteal reaction (arrowheads). Craniocaudally sequential axial CT images (bone and soft tissue windows) show cortical bone destruction and extraosseous soft tissue extension (arrowheads).. B. MRI of the left thigh. Coronal T2WFS (left) and T1WFS (right) with enhancement show an aggressive bony lesion with cortical destruction and extraosseous soft tissue mass (arrowheads).. C. MRI with DWI of the left thigh. Axial T2W FS image shows a heterogeneously hyperintense mass compared to signal intensity of adjacent muscles (arrowhead). The axial T1W FS image shows an iso-to-hyperintense mass with heterogeneous enhancement (arrowhead). Axial T1W FS image with enhancement shows an enhancing solid portion at the extraosseous area (arrowhead). DWI of b = 50 s/mm2 shows this tumor area with hyperintensity. DWI of b = 800 s/mm2 shows that this area remained hyperintense (arrowhead). ADC map shows this tumor area with hypointensity (arrowhead) and a mean ADC of 772 microm2/sec.. D.
  99mTc bone scan. Whole-body bone scintigraphy shows increased tracer uptake in the L3 vertebra, pelvic bones, femurs, and left tibia.. E.
  18F-FDG PET with CT. Whole-body PET imaging shows multifocal bone uptake in the sacrum of lumbar segments 3, 4, and 5, pelvic bones, femurs, tibiae, and left fibula. The SUVmax is 18.82 in the left iliac bone. The lesion shows severe cortical bone destruction with prominent extraosseous soft tissue extension (arrowheads).. F. Histopathology of a biopsy specimen. H&E x 200 image and x 400 image show high cellularity with epithelioid cells and spindle cells lining abnormally dilated vascular channels. Tumor cells show evidence of abnormal mitotic figures. Cytokeratin and vimentin staining are positive, CD31 and ERG staining are highly positive. The Ki-67 index was 53.72% (not shown). The final pathological diagnosis was an epithelioid angiosarcoma.. CE = contrast enhancement, DWI = diffusion-weighted image, ERG = ETS-related gene, FS = fat-suppressed, H&E = hematoxylin and eosin, SUVmax = maximum standardized uptake value, T1W = T1-weighted, T2W = T2-weighted
case_images: jksr-85-240-g001.jpg
case_images: PMC10864153_01_jksr-85-240-g001.jpg
case_images: F1
case_images: Plain radiographs showed multiple osteolytic lesions with ill-defined margins located both centrally and eccentrically (Fig. 1A). Lower extremity CT revealed multiple ill-defined osteolytic lesions with epicenters located in both the medullary space and cortex (Fig. 1A). MRI of both femurs revealed multiple lesions measuring less than 3.7 cm in longitudinal diameter, some of which were associated with extraosseous soft tissue mass formation (Fig. 1B). Moreover, gadolinium enhancement was heterogeneously observed on T1-weighted images (Fig. 1C). Notably, the enhanced solid portion of the lesion showed diffusion restriction with an apparent diffusion coefficient of 772 microm2/sec on the diffusion-weighted image (DWI) (Fig. 1C). Finally, a 99mTc bone scan showed multiple radionuclide uptakes involving the L3 vertebra, both pelvic bones, both femurs, and the left tibia (Fig. 1D). No other lesions, except for multifocal bone uptake in lumbar segments 3, 4, and 5, the sacrum, pelvic bones, both femurs, both tibiae, and left fibula, were identified by 18F-FDG PET (Fig. 1E). Microscopically, the resected specimen appeared to have high cellularity, with epithelioid and spindle cells lining the abnormally dilated vascular channels (Fig. 1F). However, additional immunohistochemical staining (Fig. 1F), including that for CD31 and ERG, was highly positive, and the Ki-67 index was 53.72%.