case_images: PMC11135369_01
case_images: A 61-year-old male, case of primary leiomyosarcoma of right femur. (a) Whole-body maximum intensity projection (MIP) image shows heterogeneously increased fluorodeoxyglucose (FDG) uptake in the right distal femur and multiple other foci of increased FDG uptake, (b) Axial fused positron emission tomography/computed tomography (PET-CT) image showing comminuted displaced pathological fracture of the distal shaft of the right femur with increased FDG uptake and associated intensely FDG avid soft-tissue component, consistent with the primary leiomyosarcoma in this particular case, (c) Axial fused PET-CT image of the pelvis showing FDG avid subtle sclerotic lesion in the right ala of the sacrum and right ilium suggestive of metastasis. Follow-up 18-F FDG-PET-CT study performed post 6 cycles of chemotherapy, (d) Whole body MIP image, (e) Axial fused PET-CT image showing reduction of fracture with distal femur nail and regression in the extent of soft-tissue component associated with the primary lesion, (f) Axial fused PET-CT image of pelvis showing no significant interval change in FDG avidity of lesions in right ala of the sacrum and right ilium overall suggestive of stable disease
case_images: IJNM-39-52-g001.jpg
case_images: PMC11135369_01_IJNM-39-52-g001.jpg
case_images: F1
case_images: PET/CT revealed a hypermetabolic expansile lytic lesion with soft-tissue component and comminuted displaced pathological fracture involving the distal shaft of the right femur as well as extensive skeletal metastasis [Figure 1].
case_images: (a) An intersecting fascicular pattern of spindle-shaped tumor cells with infiltration into bony trabeculae (H and E, x100), (b) Individual tumor cells showing a moderate amount of eosinophilic cytoplasm, oval nucleus, vesicular chromatin, prominent nucleoli, and moderate to marked nuclear pleomorphism and occasional multinucleation (H and E, x400), (c) These tumor cells are diffuse and strongly positive for smooth muscle actin (IHC, x400) (d) Mib1 labeling index was 30% in the highest proliferative area (IHC, x400)
case_images: IJNM-39-52-g002.jpg
case_images: PMC11135369_01_IJNM-39-52-g002.jpg
case_images: F2
case_images: Trucut biopsy was taken from the swelling and histopathological examination was suggestive of leiomyosarcoma of bone which subsequently was confirmed by positive smooth muscle actin (SMA) in an immunohistochemical panel study [Figure 2].