Dedifferentiated liposarcoma originating in the prostate: a rare case report

Fig. 1. Contrast-enhanced abdominal CT revealed a mass in the prostatic region with ill-defined borders with surrounding tissues (A). Gross examination showed an intact prostatic capsule (B). The prostatic cut surface had a fish-flesh-like texture with focal, gray-red, cystic regions (C). (A: B, bladder; P, prostate; R, rectum; SV, seminal vesicle; B&C: Lab ID: J2516796)

Fig. 2. Residual normal prostatic glands were present at the periphery (A). There was no distinct demarcation between the well-differentiated and dedifferentiated liposarcoma components, which were intermingled (B). A very limited well-differentiated liposarcoma component may still provide supporting evidence for the diagnosis of DDLPS (C). The dedifferentiated component was composed of short spindle cells with mild atypia, and mitotic figures were readily observed (D). (A-C: H&E, original magnification ×100; D: H&E, original magnification ×400)

Fig. 3. Diffuse strong positive expression of CDK4 (A). Diffuse strong positive expression of MDM2 (B). Focally positive expression of STAT6 (C). The Ki-67 proliferation index was approximately 60% (D). (A-D: immunohistochemistry, original magnification ×100)