Aggressive Prostatic Stromal Sarcoma Mimicking Benign Prostatic Enlargement in a Middle-Aged Man: A Case Report.

Prostatic stromal sarcoma is an exceptionally rare mesenchymal malignancy with aggressive behavior and poor prognosis. It often presents with nonspecific lower urinary tract symptoms, frequently mimicking benign prostatic hyperplasia. We report a 51-year-old man who presented with hematuria and long-standing obstructive urinary symptoms. Imaging revealed a massively enlarged prostate with a low prostate-specific antigen level. The findings strongly favored benign prostatic enlargement. Given the severity of bladder outlet obstruction and absence of overt radiologic malignancy, open retropubic prostatectomy was performed for presumed benign disease. Histopathological examination unexpectedly revealed prostatic stromal sarcoma, with immunohistochemistry negative for epithelial, lymphoid, and common stromal markers. Postoperative staging performed following histologic diagnosis demonstrated extensive locally advanced pelvic disease and distant pulmonary metastases within weeks of surgery. Despite surgical intervention, the patient rapidly developed locally advanced pelvic disease with pulmonary metastases and succumbed to the illness before initiation of palliative chemotherapy. This case underscores the diagnostic challenges, aggressive natural history, and limited therapeutic options for prostatic stromal sarcoma, particularly in low-resource settings, and emphasizes the need for heightened clinical suspicion and early multidisciplinary involvement when intraoperative findings are encountered.