A Large Bladder Tumor Covered With a Thick "Shell" of Necrotic Material: Misdiagnosis of a Patient With Spina Bifida.

Bladder tumor arising in a spina bifida patient is rare and may be clinically latent. We report the case of a 61-year-old female patient with spina bifida, neurogenic bladder, and a history of recurrent urinary tract infections. A B-ultrasound and non-contrast computed tomography scan did not reveal any bladder mass, but an unexplained "well-filled" bladder was observed, which was confusing as the catheter was present and open. However, a subsequent cystoscopic evaluation revealed a large bladder mass measuring 9.5 × 9.0 × 6.5 cm³, which almost filled the entire bladder. The mass had coarse and flocculent surface and seemed to be free from each observed wall of the urinary bladder. It was diagnosed as an infectious necrotic mass based on its appearance. During transurethral resection of the mass, a bladder tumor was suspected as small blood vessels and bleeding appeared within the inner layer of the mass. Pathological examination revealed necrotic material, inflammatory cells, and urothelial carcinoma cells. Then, a radical cystectomy was performed, and the pathological results indicated stage pT3bN0M0 transitional cell carcinoma. In the gross specimen, the base of the tumor measured 3 × 3 cm² on the top of the back wall of the bladder. Bladder tumors may have atypical presentations in patients with spina bifida. Regular screening is helpful for earlier detection and improving outcomes of bladder tumors in such patients.