BACKGROUND: Small cell carcinoma of the urinary bladder is a rare and aggressive form of bladder cancer that mainly presents at an advanced stage. As a result of its rarity, it has been described in many case reports and reviews but few retrospective and prospective trials, showing there is no standard therapeutic approach. In the literature the best therapeutic strategy for limited disease is the multimodality treatment and most authors have extrapolated treatment algorithms from the therapy recommendations of small cell lung cancer.

CASE REPORT: A 71-year-old male patient was referred to our hospital with gross hematuria and dysuria. Imaging and cystoscopy revealed a vegetative lesion of the bladder wall. A transurethral resection of the bladder was performed. Pathological examination revealed a pT2 high-grade urothelial carcinoma with widespread neuroendocrine differentiation. Multimodal treatment with neoadjuvant platinum-based chemotherapy was performed. A CT scan performed after chemotherapy demonstrated a radiological complete response. The patient underwent radical cystectomy and lymphadenectomy. The histopathological finding of bladder and node specimen confirmed a pathological complete response. A post-surgery CT scan showed no evidence of local or systemic disease. Six months after surgery, the patient is still alive and disease-free.

CONCLUSIONS: A standard treatment strategy of small cell cancer of the urinary bladder is not yet well established, but a multimodal treatment of this disease is the best option compared to surgical therapy alone. The authors confirm the use of neoadjuvant chemotherapy in limited disease of small cell carcinoma of the urinary bladder.

Keywords: Antineoplastic Combined Chemotherapy Protocols - therapeutic use, Carcinoma, Small Cell - therapy, Cystectomy, Neoadjuvant Therapy, Urinary Bladder Neoplasms - therapy