Prognostic value of combined tumor regression grade and TNM stage in muscle-invasive bladder cancer treated with neoadjuvant chemotherapy and radical cystectomy.

Introduction: Tumor regression grade (TRG) is a recognized prognostic marker in several solid tumors treated with neoadjuvant therapy, but its clinical relevance in muscle-invasive bladder cancer (MIBC) remains under investigation. This study aimed to evaluate the prognostic value of TRG and its integration with pathological TNM staging in patients with MIBC treated with neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC).

Materials and methods: We conducted a retrospective analysis of 51 patients with MIBC who received platinum-based NAC followed by RC and lymphadenectomy between 2013 and 2024. TRG was assessed according to the Fleischmann classification and combined with ypTNM stage to categorize patients as complete, partial or non-responders. Overall survival (OS) and disease-free survival (DFS) were estimated using Kaplan-Meier analysis, and independent prognostic factors were identified through Cox regression models.

Results: Complete response (ypT≤1, ypN0, TRG1) was observed in 43.1% of patients. Median OS was 19 months, with 3- and 5-year OS rates of 28.6% and 14.3%, respectively. Complete responders demonstrated significantly improved OS and DFS (p<0.001). On multivariable analysis, absence of nodal involvement (p=0.047) and complete response (p=0.012) were independently associated with better OS. Negative surgical margins showed a trend toward improved survival (p=0.064).

Conclusions: TRG is a reproducible and clinically meaningful histopathologic scoring system that enhances prognostic stratification when combined with pathological TNM staging. Its integration into routine post-NAC assessment may improve postoperative decision-making and help identify patients who could benefit from tailored surveillance or adjuvant strategies.