Evaluating Neoadjuvant Immunochemotherapeutic Response for Bladder Carcinoma Using Amide Proton Transfer-Weighted MRI

Lingmin Kong; Bei Weng; Qian Cai; Ling Ma; Wenxin Cao; Yanling Chen; Long Qian; Yan Guo; Junxing Chen; Huanjun Wang

doi:10.1016/j.acra.2024.11.060

Evaluating Neoadjuvant Immunochemotherapeutic Response for Bladder Carcinoma Using Amide Proton Transfer-Weighted MRI

Acad Radiol. 2025 Jan 9:S1076-6332(24)00934-6. doi: 10.1016/j.acra.2024.11.060. Online ahead of print.

Authors

Lingmin Kong¹, Bei Weng¹, Qian Cai¹, Ling Ma¹, Wenxin Cao¹, Yanling Chen¹, Long Qian², Yan Guo¹, Junxing Chen³, Huanjun Wang⁴

Affiliations

¹ Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou, 510080, Guangdong, PR China (L.K., B.W., Q.C., L.M., W.C., Y.C., Y.G., H.W.).
² Department of Biomedical Engineering, College of Engineering, Peking University, Beijing, China (L.Q.).
³ Department of Urology, The First Affiliated Hospital, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou, 510080, Guangdong, PR China (J.C.).
⁴ Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58 Zhongshan Road 2, Guangzhou, 510080, Guangdong, PR China (L.K., B.W., Q.C., L.M., W.C., Y.C., Y.G., H.W.). Electronic address: wanghj45@mail.sysu.edu.cn.

PMID: 39794161
DOI: 10.1016/j.acra.2024.11.060

Abstract

Rationale and objectives: To investigate the feasibility of amide proton transfer-weighted (APTw) and diffusion-weighted MRI in evaluating the response of bladder cancer (BCa) to neoadjuvant immunochemotherapy.

Materials and methods: From June 2021 to July 2023, participants with pathologically confirmed BCa were prospectively recruited to undergo MRI examinations, including APTw and diffusion-weighted MRI before and after neoadjuvant immunochemotherapy. Histogram analysis features (mean, median, and entropy) were extracted from pre- and post-treatment APTw and apparent diffusion coefficient (ADC) maps, respectively. Participants were categorized into pCR (pathological complete response, no residual tumor) and non-pCR groups based on histologic evaluation of post-treatment cystectomy specimens. The diagnostic efficacy of parameters in predicting tumor responsiveness was evaluated by calculating the area under receiver operating characteristic curve (AUC).

Results: Significant differences were found in several imaging biomarkers derived from pre-treatment APTw and diffusion-weighted MRI (P<0.05 for all). The baseline APTw mean values yielded the highest diagnostic performance, with an AUC of 0.85 (AUC: 0.75-0.93), for evaluating tumor responsiveness. For the pCR group, APTw values markedly decreased while ADC values noticeably increased at post-treatment MRI (P<0.05 for all). However, the parameter changes in non-pCR group were not significant (P>0.05 for all).

Conclusion: MRI parametrics derived from APTw and diffusion-weighted MRI can both serve as valuable noninvasive imaging biomarkers for evaluating the efficacy of immunochemotherapy and may be used to guide personalized precision therapy.

Keywords: Amide proton transfer-weighted imaging; Bladder cancer; Chemotherapy; Diffusion-weighted imaging; Immunotherapy.