Abstract
INTRODUCTION: Radical cystectomy is the standard treatment for muscle-invasive bladder cancer. A neobladder is created as part of urinary diversion; however, the formation of bladder stones is often a late complication-related concern. CASE PRESENTATION: A 56-year-old man underwent radical cystectomy and neobladder construction for bladder cancer 25 years ago. A huge neobladder stone was diagnosed when the patient developed a strangulated ileus. Open surgery was performed to remove the bladder stone. The stone's size was 21.6 × 15.5 × 18.5 cm and its weight was 5 kg. CONCLUSION: To the authors' knowledge, this is the largest case of bladder calculus reported to date.