The Value of Magnetic Resonance Imaging-Driven Apparent Diffusion Coefficient to Predict Pathologic Response of Neoadjuvant Chemotherapy in Muscle-Invasive Bladder Cancer: A Single-Center Retrospective Study
10.22465/juo.255000280014
- Author:
Hyungwoo AHN
1
;
Sung Il HWANG
;
Hak Jong LEE
;
Kyu Sang LEE
;
Sung Kyu HONG
;
Seok-Soo BYUN
;
Sangchul LEE
;
Jong Jin OH
Author Information
1. Department of Radiology, Seoul National University Bundang Hospital, Seoul National College of Medicine, Seoul, Korea
- Publication Type:Original Article
- From:
Journal of Urologic Oncology
2025;23(2):198-206
- CountryRepublic of Korea
- Language:English
-
Abstract:
Purpose:This study aimed to evaluate the predictive value of apparent diffusion coefficient (ADC) values from magnetic resonance imaging (MRI) in assessing pathologic response to neoadjuvant chemotherapy (NAC) in patients with muscle-invasive bladder cancer (MIBC) and the optimal cutoff value of ADC for predicting NAC response.
Materials and Methods:Among 582 patients who underwent radical cystectomy between December 2011 and December 2024, we included 146 patients who received preoperative NAC and pretreatment MRI. Pathologic response was determined based on the surgical pathology results: patients with pathologic stage >pT2 and/or presence of nodal involvement (N+) were classified as nonresponders, while those with ≤pT2 and no nodal involvement (N0) were classified as responders. MRI-derived ADC values were compared between the 2 groups. The receiver operating characteristic (ROC) curve was used to determine the optimal cutoff value for predicting NAC response. Multivariate logistic regression analysis using preoperative parameter was performed and Kaplan-Meier survival analysis were utilized to assess overall survival (OS) and cancer-specific survival (CSS) according to NAC response.
Results:Among the 146 patients, 90 (61.6%) were classified as responders, 56 (38.4%) were nonresponders. The mean ADC value was significantly higher in responders (1,100.35±249.12 mm2/sec) than in nonresponders (763.95±118.97 mm2/sec, p<0.001). ROC analysis demonstrated an area under the curve of 0.69, with an optimal cutoff value of 845.0 mm2/sec. Multivariate logistic regression identified ADC value as an independent predictor of NAC response (odds ratio, 1.025; 95% confidence interval, 1.006–1.043; p=0.008). During median follow-up 30.3 months, Kaplan-Meier analysis revealed that responders had significantly better 5-year OS (80.8% vs. 45.9%) and 5-year CSS (92.6% vs. 54.5%), with log-rank test p<0.001.
Conclusion:MRI-derived ADC values are a reliable imaging biomarker for predicting pathologic response to NAC in MIBC. Further validation in large-scale prospective studies is required to confirm these findings.
