A Case of Urothelial Carcinoma With Squamous Differentiation of the Bladder, Infiltrating the Small Intestine and Rectus Abdominis, Treated With the Use of a Short Gracilis Myocutaneous Flap.

Introduction: Squamous differentiation (SD) occurs in up to 20% of muscle invasive bladder cancers.

Case Presentation: An 85-year-old man with an intrapelvic mass invading the bladder, small intestine, and rectus abdominis presented to our department. Cystoscopy showed a necrotic mass at the dome of the bladder. Histopathological examination of specimens from transurethral resection indicated squamous cell carcinoma. Radical cystectomy with resection of the small intestine and rectus abdominis, and reconstruction of the abdominal wall using a left short gracilis myocutaneous flap was performed. The histopathology showed squamous cell carcinoma and urothelial carcinoma (UC) components; findings consisted of UC with SD. The patient received appropriate flap management and treatment for postoperative complications and was discharged on postoperative Day 100.

Conclusion: To our knowledge, this is the first report of an invasive bladder cancer with SD treated with the use of a short gracilis myocutaneous flap.