Abstract
INTRODUCTION: Small cell carcinoma of the bladder (SCCB) is a rare and aggressive disease with no established standard treatment. We report a case of SCCB that initially progressed with chemotherapy but responded well to a combination of chemotherapy and radiotherapy. CASE PRESENTATION: A 62-year-old man presented with painless gross hematuria. Transurethral resection of the bladder tumor (TURBT) confirmed SCCB. Gemcitabine-carboplatin (GEM-CBDCA) and pembrolizumab were ineffective, leading to rapid tumor progression. The patient developed bladder tamponade and obstructive renal failure. Emergency radiotherapy (30 Gy) controlled bleeding, and etoposide-carboplatin chemotherapy resulted in significant tumor shrinkage. CONCLUSION: This case highlights the potential effectiveness of etoposide-carboplatin and radiotherapy in SCCB, especially in cases resistant to other treatments. Further studies are needed to establish optimal treatment strategies for SCCB.