Final Pathological Stage after Neoadjuvant Chemotherapy and Radical Cystectomy for Bladder Cancer-Does pT0 Predict Better Survival than pTa/Tis/T1?

Abstract

Purpose: We assessed survival dependent on pathological response after neoadjuvant chemotherapy in a large multicenter patient cohort, with a particular focus on the difference between the absence of residual cancer (pT0) and the presence of only nonmuscle invasive residual cancer (pTa, pTis, pT1).

Materials and methods: We retrospectively reviewed records of patients with urothelial cancer who received neoadjuvant chemotherapy and underwent radical cystectomy at 19 contributing institutions from 2000 to 2013. Patients with cT2-4aN0M0 and eventual pN0 disease were selected for this analysis. Estimated overall survival was compared between patients with pT0 and pTa/Tis/T1 disease. A multivariable Cox proportional hazards regression model for overall survival was generated to evaluate hazard ratios for variables of interest.

Results: Of 1,543 patients treated with neoadjuvant chemotherapy and radical cystectomy during the study period 257 had pT0N0 and 207 had pTa/Tis/T1N0 disease. The Kaplan-Meier mean estimates of overall survival for pT0 and pTa/Tis/T1 cases were 186.7 months (95% CI 145.9-227.6, median 241.1) and 138 months (95% CI 118.2-157.8, median 187.4), respectively (p=0.58). In the Cox proportional hazards regression model for overall survival pTa/Tis/T1N0 status (HR 0.36, 95% CI 0.23-0.67) and pT0N0 status (HR 0.28, 95% CI 0.17-0.47) compared to pT2N0 pathology, positive surgical margin (HR 1.75, 95% CI 1.07-2.86), and receiving a methotrexate, vinblastine, doxorubicin and cisplatin regimen compared to an "other" regimen (HR 0.45, 95% CI 0.27-0.76) were predictors of overall survival.

Conclusions: pTa/Tis/T1N0 and pT0N0 stage on the final cystectomy specimen are strong predictors of survival in patients treated with neoadjuvant chemotherapy and radical cystectomy. We did not discern a statistically significant difference in overall survival when comparing these 2 end points.

Keywords: cystectomy; drug therapy; neoadjuvant therapy; urinary bladder neoplasms.