Residual tumor discovered in routine second transurethral resection in patients with stage T1 transitional cell carcinoma of the bladder.

When a second transurethral resection was routinely performed 8 to 14 days after the initial transurethral resection in 46 patients for stage T1 bladder tumors residual disease was found in 20 despite the surgical report of complete resection in 40. In only 13 patients was residual tumor noted at repeat resection by the senior urologist performing the operation and residual tumor was confirmed histologically in 10 of them. The extent of the lesion is easily misjudged even by experienced surgeons. Early cystoscopy cannot exclude residual tumor. Residual tumor is an important cause of early recurrence and repeat resection of stage T1 lesions is recommended.