BACKGROUND: Neoadjuvant chemoradiotherapy followed by radical surgery has been a common practice for patients with locally advanced rectal cancer, but the response rate varies among patients. This study aimed to develop a ResNet-Vision Transformer based magnetic resonance imaging (MRI)-endoscopy fusion model to precisely predict treatment response and provide personalized treatment. METHODS: In this multicenter study, 366 eligible patients who had undergone neoadjuvant chemoradiotherapy followed by radical surgery at eight Chinese tertiary hospitals between January 2017 and June 2024 were recruited, with 2928 pretreatment colonic endoscopic images and 366 pelvic MRI images. An MRI-endoscopy fusion model was constructed based on the ResNet backbone and Transformer network using pretreatment MRI and endoscopic images. Treatment response was defined as good response or non-good response based on the tumor regression grade. The Delong test and the Hanley-McNeil test were utilized to compare prediction performance among different models and different subgroups, respectively. The predictive performance of the MRI-endoscopy fusion model was comprehensively validated in the test sets and was further compared to that of the single-modal MRI model and single-modal endoscopy model. RESULTS: The MRI-endoscopy fusion model demonstrated favorable prediction performance. In the internal validation set, the area under the curve (AUC) and accuracy were 0.852 (95% confidence interval [CI]: 0.744-0.940) and 0.737 (95% CI: 0.712-0.844), respectively. Moreover, the AUC and accuracy reached 0.769 (95% CI: 0.678-0.861) and 0.729 (95% CI: 0.628-0.821), respectively, in the external test set. In addition, the MRI-endoscopy fusion model outperformed the single-modal MRI model (AUC: 0.692 [95% CI: 0.609-0.783], accuracy: 0.659 [95% CI: 0.565-0.775]) and the single-modal endoscopy model (AUC: 0.720 [95% CI: 0.617-0.823], accuracy: 0.713 [95% CI: 0.612-0.809]) in the external test set. CONCLUSION The MRI-endoscopy fusion model based on ResNet-Vision Transformer achieved favorable performance in predicting treatment response to neoadjuvant chemoradiotherapy and holds tremendous potential for enabling personalized treatment regimens for locally advanced rectal cancer patients.
Humans ; Rectal Neoplasms/diagnostic imaging* ; Magnetic Resonance Imaging/methods* ; Male ; Female ; Middle Aged ; Neoadjuvant Therapy/methods* ; Aged ; Adult ; Chemoradiotherapy/methods* ; Endoscopy/methods* ; Treatment Outcome

Objective To observe the MRI findings of normal pancreas in piglets. Methods Eight healthy piglets underwent MR examination, and the morphology, size, signal intensity of pancreas were observed. After MR imaging, all piglets were abdominally incised to observe the anatomy of pancreas and pancreatic adjacent structures. The opening of both common bile duct and pancreatic duct were detected during operation. Two piglets were sacrificed after operation and the whole pancreases were dissected for anatomic research. Results The pancreas of piglets was composed of three parts: right lobe, median lobe and left lobe. All the lobes were displayed clearly on MRI. The signal intensity of pancreas was higher than that of liver and spleen on T1WI, whereas lower than that of liver and spleen on T2WI. On MRCP, pancreatic duct was not presented, whereas the common bile duct could be seen clearly. The opening of common bile duct located at superior part of duodenum (nearby the pylorus) and the opening of pancreatic duct situated at duodenal papilla corresponding to pancreatic right lobe. Conclusion MRI can show the pancreas of piglets very well. The morphology of pancreas and features of common bile duct conjunction with pancreatic duct in piglet are different from those in human.

Objective To explore the feasibility,safety,efficacy and mechanism of intraoperative regional chemotherapy of advanced gastric cancer. Methods The related literatures were reviewed and analyzed. Results Compared with systemic chemotherapy,intraoperative regional chemotherapy of advanced gastric cancer could increase blood drug concentration of cancerous tissue,reduce the systemic toxic side effects,increase survival rate and improve the quality of life. Conclusion Intraoperative regional chemotherapy,as an adjuvant treatment of advanced gastric cancer,has been gradually applied to clinic because of the definite curative effect,which is worth popularizing. However,it needs systemic researches and accumulation of cases.