Analysis of risk factors for cancer-specific survival in neoadjuvant chemotherapy nonresponsive disease of muscle-invasive bladder cancer: A multicentre study from the Turkish Urooncology Association Bladder Tumor study group.

Objective: To investigate the risk factors affecting cancer-specific survival (CSS) in nonresponsive disease to neoadjuvant chemotherapy (NAC) among patients with muscle-invasive bladder cancer (MIBC) who were treated with NAC and radical cystectomy (RC).

Methods: Patients with MIBC who underwent NAC and RC were retrospectively examined. By comparing clinical and pathological stages, patients whose pathological stage was lower than clinical stage were categorized as "NAC-responsive" and the remainder as "NAC-non-responsive." Apart from pathologic staging, variables compared between groups included age, gender, Eastern Cooperative Oncology Group (ECOG) score, clinical stages, NAC type and cycle number, durations between MIBC diagnosis and NAC initiation and RC, presence of hydronephrosis, number of lymph nodes removed, and variant histology of urothelial bladder cancer. CSS analysis was performed by construction of Kaplan-Meier survival curves and multivariable Cox regression was performed to identify the prognosticators in the NAC-non-responsive-group.

Results: Ninety-two patients were included with a mean age was 61.5 ± 8.5 years, of whom 84.8% were men. The NAC regimen used was predominantly gemcitabine-cisplatin (88%) and the median cycle number was 4. Fifty-six (60.9%) patients were NAC-non-responsive. There was a significantly lower proportion of patients receiving ≥4 cycles (46.4% vs. 66.7%) and a higher rate of patients with ECOG score ˃1 (33.9% vs. 11.1%) in the NAC-non-responsive-group compared to the NAC-responsive-group (both P < 0.05). Other variables were similar between groups. In multivariable analysis, only ypN+ was found to be an independent prognosticator for CSS in NAC-non-responsive-group (HR: 2.725, CI95%:1.017-7.303).

Conclusion: Although higher ECOG scores and lower cycle numbers appears to be associated factors in NAC-non-responsive disease, only ypN(+) status was a prognosticator for CSS in this population.