Transurethral resection of bladder tumor (TURBT) accounts for much of the pathologic response in patients with muscle-invasive bladder cancer (MIBC) receiving neoadjuvant chemotherapy (NAC) and TURBT prior to radical cystectomy, according to findings presented Friday at the 2016 Genitourinary Cancers Symposium in San Francisco.
“An understanding of which patients are true responders to chemotherapy and which receive a therapeutic TURBT is needed to select optimal candidates for NAC,” concluded investigators led by Trinity J. Bivalacqua, MD, PhD, of Johns Hopkins University in Baltimore.
Dr. Bivalacqua and colleagues studied down-staging at cystectomy in patients with clinical stage 2 urothelial carcinoma. Of 328 patients from their institution, 172 received NAC and TURBT and 156 received only TURBT prior to radical cystectomy.
Pathologic response was higher in NAC patients compared with non-NAC patients (62% vs. 21%). The researchers discovered that NAC patients were significantly younger than non-NAC patients (64.8 vs. 71.2 years), with higher body mass index (28.1 vs. 26.7 kg/m2), lower frequency of Charlson comorbidity scores of 3 or greater (13.4% vs. 26.7%), and fewer instances of prior non-muscle invasive bladder cancer (9.4% vs. 22.4%). After adjustment for these factors (as well as race, gender, time, and smoking status), NAC patients were 2.5 times as likely as non-NAC patients to have a pathologic response.
Using the model, the investigators determined that in patients who receive NAC, 40% of pathologic response can be attributed to TURBT.