Predicting Response to Neoadjuvant Chemotherapy in Bladder Cancer

Abstract Context Neoadjuvant chemotherapy (NAC) is recommended prior to radical cystectomy in the setting of muscle-invasive bladder cancer. Despite a 5–10% survival benefit, some patients do not respond to NAC. Identification of the nonresponders could avoid side effects and delay in surgery. Objective The objective of this review is to summarize the latest evidence regarding predictors of NAC response. Evidence acquisition MEDLINE, Embase, and the Cochrane Library databases were searched for published studies including clinical, pathological, molecular, and imaging tests or factors that can be applied before or during NAC to predict its results. Evidence synthesis Patient characteristics and imaging techniques seem to have minimal utility to predict NAC response. Only advanced magnetic resonance imaging techniques seem to have a potential role. There is insufficient evidence to suggest a change in NAC paradigm for variant histology, whereas the most promising results come from molecular characterization of tumors. Conclusions No validated instrument currently exists to predict NAC response. While awaiting further evidence, no strong recommendation can be made toward a shift in paradigm. Patient summary The most effective and aggressive treatment for muscle-invasive bladder cancer is radical cystectomy preceded by effective neoadjuvant chemotherapy. In this paper, we reviewed the current literature and published evidence to identify predictors of response to neoadjuvant chemotherapy for muscle-invasive bladder cancer. To date, no instrument exists to predict which patients will respond to neoadjuvant chemotherapy.