Effectiveness of Neoadjuvant Chemotherapy for Muscle-invasive Bladder Cancer in the Current Real World Setting in the USA

Abstract

BackgroundThe use of neoadjuvant chemotherapy (NAC) before radical cystectomy (RC) is supported by results from several randomized control trials, including SWOG-8710. ObjectiveTo look at the effectiveness of NAC before RC in current real world practice in the USA. Design, setting, and participantsWe used the National Cancer Data Base (NCDB) to identify patients with nonmetastatic muscle-invasive urothelial carcinoma of the bladder who underwent RC between 2004 and 2012. InterventionReceipt of NAC before RC. Outcome measurements and statistical analysisThe primary endpoint was overall survival (OS). Secondary endpoints were rates of complete pathologic response (pT0), positive pathologic lymph nodes (pN+), and margin status. Using a landmark analysis to adjust for an immortal-time bias, OS comparison was performed using Cox regression analysis. Furthermore, logistic regression models examining secondary outcomes were fitted. To adjust for potential selection bias, propensity score–weighted analyses were performed. Results and limitationsOf 8732 patients who underwent RC, 1619 (19%) received NAC. Following propensity score adjustment, receipt of NAC was not associated with an OS benefit (hazard ratio 0.97; p=0.591). On secondary outcome analysis, higher pT0 rates (odds ratio 5.03; p<0.001) were recorded among patients who received NAC, although rates of pT0 were lower than for patients treated with NAC within the SWOG-8710 trial (13% vs 38%). Limitations include the retrospective design and limited details available regarding type of chemotherapy. ConclusionsImportant baseline differences between patients from the SWOG-8710 trial and those in general urologic practice exist. After adjusting for immortal-time bias, we did not find a clear survival advantage of NAC before RC when compared to RC alone in current general urology practice in the USA. Patient summaryThe benefit of chemotherapy before radical cystectomy is supported by few randomized control trials. In this study, using a large national data set from the USA we found that preoperative chemotherapy is not associated with a survival benefit in all patients in general urology practice. Hence, better selection criteria are needed to determine who will benefit the most from chemotherapy before radical cystectomy.