Dr. Horiguchi and colleagues studied the patients between March 2005 and June 2018, who were administered platinum-based neoadjuvant chemotherapy followed by radical cystectomy in 254 patients with T2-4NxM0 MIBC. After diagnostic transurethral resection of bladder tumor (TURBT), all participants received two courses of gemcitabine plus cisplatin (GCis) or gemcitabine plus carboplatin (GCb) based on cisplatin eligibility. Quantitative radiologic response was measured by RECIST ver. 1.1 using a contrast-enhanced computed tomography (CT). RC and bilateral pelvic lymphadenectomy were performed approximately within 90 days after the initial diagnosis of MIBC. Multivariate logistic regression analysis was applied to develop the nomogram for pT0 prediction.
Dr. Horiguchi then summarized the results of their study. Median age and follow-up periods were 68 years and 50 months, respectively. The number of patients with GCis and GCb were 57 (22%) and 197 (78%), respectively. Of 254, 24 (9.5%), 89 (35%), 69 (27), and 7 (2.7%) patients achieved radiologic complete response (CR), partial response (PR), stable disease (SD), and progression disease (PD), respectively. Also, 65 (26%) patients who underwent complete TURBT (cTURBT) remain undetectable tumor after NAC. 89 patients with CR + cTURBT (CR group) were potential candidates for bladder preservation therapy. After RC, 65 (26%) patients achieved pT0. The pT0 rate in CR, PR, SD and PD groups were 51%, 52%, 17%, 7.2%, and 0%, respectively. Multivariate logistic regression analysis showed that male, orthotopic ileal neobladder reconstruction, CR group were a significant factor for pT0. The nomogram for predicting pT0 probability showed significant association with actual pT0 rate (c-index = 0.812).
Dr. Horiguchi concluded his talk with a summary that although CR group significantly contributed to pT0 rate, the residual tumor remains in half of the patients with CR after NAC. Careful selection for bladder preservation therapy is necessary to avoid under treatment and/or overtreatment in patients with CR after NAC.
Presented by: Hirotaka Horiguchi, Hirosaki University, Japan
Written by: Abhishek Srivastava, MD, Society of Urologic Oncology Fellow, Fox Chase Cancer Center, Fox Chase Cancer Center, Philadelphia, PA, Twitter:@shekabhishek at the American Urological Association's 2019 Annual Meeting (AUA 2019), May 3 – 6, 2019 in Chicago, Illinois