Neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC) in patients with non-metastatic muscle-invasive bladder cancer (MIBC) confers an absolute survival benefit of 5-10%. There is evidence that molecular differences between tumors may impact response to therapy, highlighting a need for clinically validated biomarkers to predict response to NAC.
Four bladder cancer cohorts were included. Inverse probability weighting was used to make baseline characteristics (age, sex, and clinical tumor stage) between NAC-treated and untreated groups more comparable. Molecular subtypes were determined using a commercial genomic subtyping classifier. Survival rates were estimated using weighted Kaplan Meier (KM) curves. Cox proportional hazards (PH) models were used to evaluate the primary and secondary study endpoints of overall survival (OS) and cancer-specific survival (CSS), respectively.
A total of 601 patients with MIBC were included, where 247 had been treated with NAC and RC and 354 underwent RC without NAC. With NAC, the overall net benefit to OS and CSS at three years was 7% and 5%, respectively. After controlling for clinicopathologic variables, non-luminal tumors had greatest benefit from NAC with 10% greater OS at 3 years (71% vs 61%) while luminal tumors had minimal benefit (63% vs 65%) for NAC vs. non-NAC, respectively.
In patients with MIBC, a commercially available molecular subtyping assay revealed non-luminal tumors received the greatest benefit from NAC, while patients with luminal tumors experienced a minimal survival benefit. A genomic classifier may help identify patients with MIBC who would benefit most from NAC.
The Journal of urology. 2021 Oct 13 [Epub ahead of print]
Yair Lotan, Joep de Jong, Vinnie Y T Liu, Tarek A Bismar, Stephen A Boorjian, Huei-Chung Huang, Elai Davicioni, Omar Y Mian, Jonathan L Wright, Andrea Necchi, Marc A Dall'Era, Hristos Z Kaimakliotis, Peter C Black, Ewan A Gibb, Joost Boormans
Department of Urology, University of Texas Southwestern Medical Center, Dallas Texas., Department of Urology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands., Veracyte Inc., Vancouver, British Columbia., Department of Pathology and Laboratory Medicine, University of Calgary, Cumming School of Medicine, Calgary, AB., Mayo Clinic, Rochester, Minnesota., Department of Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, Ohio., Department of Urology, University of Washington School of Medicine, Fred Hutchinson Cancer Research Center, Seattle, Washington., Vita-Salute San Raffaele University, Milan, Italy., Department of Urologic Surgery, UC Davis Health, Davis, California., Department of Urology, Indiana University, Indianapolis, Indiana., Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia.