case_images: PMC10857886_01
case_images: A. Coronal view of MRI shows a well-defined hyper-intense soft tissue mass with marked enhancement at the lateral lower left thigh. B. Axial view of MRI shows no evidence of local bone invasion
case_images: cureus-0016-00000051981-i01.jpg
case_images: PMC10857886_01_cureus-0016-00000051981-i01.jpg
case_images: FIG1
case_images: MRI imaging showed a 7 cm markedly enhancing, well-defined solid soft tissue mass that abutted the lateral aspect of the lower vastus lateralis muscle (Figure 1A). There was no evidence of local bone invasion or distant metastasis (Figure 1B).
case_images: A. Cellular well-circumscribed neoplasm (H&E x4). B. Focal infiltration into adjacent fibroconnective tissue (arrow) (H&E x10).
case_images: cureus-0016-00000051981-i02.jpg
case_images: PMC10857886_01_cureus-0016-00000051981-i02.jpg
case_images: FIG2
case_images: Scanning power microscopy demonstrated a non-encapsulated densely cellular neoplasm with focal infiltration into adjacent fibroconnective tissue (Figure 2A, 2B).
case_images: Intermediate power view. Areas of high cellularity with spindle cells arranged in short intersecting fascicles (H&E x10).
case_images: cureus-0016-00000051981-i03.jpg
case_images: PMC10857886_01_cureus-0016-00000051981-i03.jpg
case_images: FIG3
case_images: The tumor was composed of monomorphic cells, which were spindle to ovoid in shape and arranged in short intersecting fascicles (Figure 3).
case_images: High power view: The tumor is composed of spindle (A) to more ovoid (B) cells with uniform nuclei and inconspicuous nucleoli in a collagenized stroma (H&E x40).
case_images: cureus-0016-00000051981-i04.jpg
case_images: PMC10857886_01_cureus-0016-00000051981-i04.jpg
case_images: FIG4
case_images: On higher magnification, the tumor cells were seen to have uniform nuclei with variable nucleoli embedded in the collagenous stroma (Figure 4A, 4B).
case_images: A. Small thin-walled vascular channels with chronic inflammatory infiltrate composed of lymphocytes. (B) Occasional eosinophils (arrow). (C) Markedly dilated and irregular blood vessels (H&E x40).
case_images: cureus-0016-00000051981-i05.jpg
case_images: PMC10857886_01_cureus-0016-00000051981-i05.jpg
case_images: FIG5
case_images: In some areas, the tumor cells were arranged haphazardly and contained ectatic/angulated thin-walled blood vessels (Figure 5A, 5C). Focal tumor-infiltrating lymphocytes were noted with occasional eosinophils (Figure 5A, 5B, 5C).
case_images: A. Foci of necrosis. B. Mitotic figures easily identified (arrow) (H&E x40).
case_images: cureus-0016-00000051981-i06.jpg
case_images: PMC10857886_01_cureus-0016-00000051981-i06.jpg
case_images: FIG6
case_images: Mitotic figures were readily seen (11 per 10 high-power fields) with scattered foci of necrosis (Figure 6A, 6B).