Two Faces of Malignancy in One Prostate: A Rare Coexistence of Adenocarcinoma and Leiomyosarcoma

Adenocarcinoma is the predominant malignant tumor of the prostate, while primary prostatic leiomyosarcoma is an exceptionally rare and highly aggressive mesenchymal neoplasm. The synchronous presence of both entities is extremely uncommon and has been, to our knowledge, described in only a few cases. We describe a 50-year-old man with persistent lower urinary tract symptoms and mildly elevated prostate-specific antigen. Imaging demonstrated two distinct intraglandular lesions. Histopathology and immunohistochemistry confirmed acinar adenocarcinoma and leiomyosarcoma in separate foci. Laparoscopic radical prostatectomy was performed; positive sarcomatous margins prompted adjuvant radiotherapy. Integrated clinical, radiologic, and pathologic assessment is essential for accurate diagnosis and management. • An exceptionally rare coexistence of prostatic adenocarcinoma and leiomyosarcoma • MRI detected two lesions but could not distinguish epithelial vs mesenchymal cancer • Immunohistochemistry confirmed distinct foci: SMA/desmin+ leiomyosarcoma and PSA/CK+ adenocarcinoma • Radical prostatectomy plus adjuvant EBRT achieved early local control at 6 months • Emphasizes combined PSA, imaging, histology and immunohistochemistry for atypical prostate tumors