Prognosis of patients with T1 bladder cancer after en bloc transurethral resection of bladder tumor stratified by invasion to the level of the muscularis mucosa.

This is the first study evaluating the prognosis by T1 substaging based on invasion to the MM level using ERBT specimens. ERBT provided high-quality specimens for diagnosing the MM and showed poor prognosis in pT1c bladder cancer. ERBT could be an appropriate surgical approach for an accurate diagnosis and prognosis of the T1 bladder cancer substage.