Dose dense MVAC prior to radical cystectomy: a real-world experience.

Purpose: Our primary endpoint was to assess pathological response rate (pT0N0 and ≤pT1N0) for patients with BCa treated with the accelerated or dose dense MVAC (ddMVAC) chemotherapy followed by radical cystectomy (RC) in this real-word multi-institutional cohort.

Materials And Methods: We retrospectively reviewed records of patients with urothelial cancer who underwent ddMVAC and RC at seven contributing institutions from 2000 to 2015. Patients with cT2-4a, M0 BCa were included. Presence of cT3-4 disease, hydronephrosis, lymphovascular invasion and/or existence of sarcomatoid, or micropapillary features on the initial transurethral resection of bladder tumor specimen was defined as high-risk disease. Logistic regression models for prediction of pT0N0 and ≤pT1N0 were generated for the entire cohort as well as for the cN0 subgroup. The multivariable Cox proportional hazards regression model for survival using post RC data was used to assess hazard ratios (HRs) for the variables of interest.

Results: A total of 345 patients received ddMVAC chemotherapy during the study period; 85% had high-risk features. The median number of chemotherapy cycles was 4 (IQR 4-4); >90% of patients completed all scheduled cycles. The observed rates of pT0N0 and ≤pT1N0 were 30.4 and 49.3%, respectively, among cN0 patients. On the multivariable regression model, the presence of more than one clinical high-risk element was associated with 70% [OR 0.30 95% CI (0.10-0.86); p = 0.02] reduction in the odds of achieving partial pathological response.

Conclusions: A complete response (pT0N0) was observed in one-third of patients after neoadjuvant ddMVAC therapy, and a partial response (≤pT1N0) was observed in nearly half of the cases in this real-world experience with this regimen. To our knowledge, this represents the largest experience outside clinical trial settings.