Secondary Prostate Lymphoma Mimicking Prostate Cancer Successfully Managed by Transurethral Resection to Relieve Urinary Retention.

Secondary lymphoma of the prostate is described as the involvement of the prostate gland by lymphomatous spread from a primary site. This condition is exceedingly rare and often presents diagnostic and therapeutic challenges. The symptoms often mimic those of benign prostatic hyperplasia or prostate cancer, including LUTS (lower urinary tract symptoms) and even complete urinary retention. Here, we present a rare case of a 62-year-old male patient undergoing chemotherapy for stage IV mantle cell stomach lymphoma and subsequently secondary prostatic involvement. The patient presented with complete urinary retention, accompanied by biochemical (PSA = 11.7 ng/mL) and imaging (Magnetic Resonance Imaging-PIRADS V lesion) suspicion for prostate cancer. Histopathologic analysis of the MRI-targeted prostate fusion biopsy revealed secondary prostatic lymphoma. The chosen treatment was transurethral resection of the prostate (TUR-P) for relief of symptoms, which significantly improved urinary function (postoperative IPSS = 5 and Qmax = 17 mL/s). This case underscores the importance of considering prostatic lymphoma in the differential diagnosis of bladder outlet obstruction, especially in patients with a known lymphoma history. This report also provides a focused review of the literature on secondary prostatic lymphoma, highlighting the diagnostic challenges, treatment options, and clinical outcomes.