Long-Term Survival After Definitive Concurrent Chemoradiation Therapy for Synchronous Small Cell Neuroendocrine Carcinoma of the Urinary Bladder and Adenocarcinoma of the Prostate: A Case Report.

Available reports of synchronous prostate and bladder cancer have exclusively described radical cystoprostatectomy with or without perioperative chemotherapy as the treatment of choice. There are no reports of curative intent or definitive chemoradiation therapy for synchronous primary bladder and primary prostate cancers. Small cell carcinoma of the bladder is a rare and aggressive tumor. We present the first case of synchronous mixed small cell carcinoma and urothelial carcinoma of the urinary bladder and adenocarcinoma of the prostate in a 70-year-old male who attained long-term survival after curative intent and definitive concurrent chemoradiotherapy with minimal acute and late toxicities. The patient remained alive and disease-free at 41 months post-treatment and achieved excellent functional outcomes with organ preservation. Definitive chemoradiation therapy offers a safe and effective, curative-intent organ preservation treatment for localized synchronous prostate and bladder cancers.