↓ Figure 1. A peripherally FDG-avid, centrally necrotic lesion (6.2 × 4.5 × 5.5 cm) is seen involving the posterolateral and central glands of the prostate, with significant indentation of the seminal vesicles and anterior rectal wall, and mild indentation of the bladder base. A peripheral rim of FDG uptake is noted without focal hypermetabolic activity in the central necrotic zone. No distant FDG-avid lesions are identified, consistent with localised disease at initial staging. FDG: fluorodeoxyglucose.
↓ Figure 2. Section showing malignant oval to spindle cells arranged in fascicles and sheets. The cells exhibit a moderate degree of pleomorphism with coarse, clumped chromatin; occasional cells display bizarre nuclei. These morphological features, in conjunction with the immunohistochemical profile (SMA, desmin, calponin, H-caldesmon positive; epithelial and melanocytic markers negative), are consistent with high-grade epithelioid leiomyosarcoma of the prostate. H&E stain, low power. H&E: hematoxylin and eosin; SMA: smooth muscle actin.
↓ Figure 3. Spindle-shaped tumor cells arranged in interlacing fascicles with focal whorled patterns, characteristic of leiomyosarcoma. Marked nuclear pleomorphism, hyperchromasia, and increased mitotic activity are evident. This high-power view highlights the smooth muscle differentiation pattern consistent with a diagnosis of leiomyosarcoma of the prostate. H&E stain, high power.
