The Prognostic Value of Tumor Regression Grades Combined With TNM Classification in Patients With Muscle-Invasive Bladder Cancer Who Underwent Neoadjuvant Chemotherapy Followed by Radical Cystectomy

INTRODUCTION: Tumor regression grades (TRGs) quantify the pathologic response to neoadjuvant chemotherapy (NAC). The aim of the study was to investigate the prognostic value of TRGs in combination with the TNM classification in an independent cohort of patients with muscle-invasive bladder cancer (MIBC) treated with NAC followed by radical cystectomy (RC) in a retrospective setting. PATIENTS AND METHODS: Patients treated with a complete course of NAC followed by RC for MIBC between December 2012 and December 2017 were enrolled in the study. TRGs were determined in RC specimens. Data were collected preoperatively, and the follow-up was continued up to August 2018. Kaplan-Meier curves and the Cox proportional hazards model were used to compare survival probabilities between major responders (no MIBC, < ypT2 and ypN0), partial responders (≥ ypT2 or ypN+ and TRG2), and non-responders (≥ ypT2 or ypN+ and TRG3). RESULTS: A group of 70 patients with a median age of 64 years (interquartile range, 58-67 years) was analyzed. There were 36 major responders, 21 partial responders, and 13 non-responders. In comparison with a major response, a partial response was associated with a hazard ratio of 9.44 (95% confidence interval, 1.10-80.89; P = .04) and non- responders showed a hazard ratio of 17.85 (95% confidence interval, 2.18-145.85; P = .007) for death. CONCLUSIONS: The study confirms the prognostic value of the pathologic response to NAC. Determination of TRGs is straightforward, provides valuable information, and could be easily included in the standard pathologic examination of RC surgical specimen. Prospective studies are needed to establish the role of TRG in routine clinical practice.