Objective To analyze the value of dynamic enhanced multi-slice spiral computed tomography (MSCT) combined with two-dimensional (2D) curved reconstruction technique in the differentiation of benign and malignant intraductal papillary mucinous neoplasm (IPMN) of pancreas,and compare with magnetic resonance cholangiopancreatography(MRCP).Methods MSCT and MRCP data of a total of 50 patients with IPMNs confirmed by pathology after surgery was retrospectively reviewed.The benign and malignant IPMNs were differentiated based on the presence of mural nodules,main pancreatic duct (MPD) ≥ 10 mm,septum thickness ≥2 mm,calcification,surrounding vascular infiltration,enlarged peripancreatic lymph nodules,distant metastatic lesions and maximal branch duct type IPMN lesions ≥30 mm shown in the images.The sensitivity,specificity and accuracy were calculated and the receiver-operating-characteristics (ROC) analysis were drawn.Area under the curve (AUC) was calculated.Results Mural nodules in MSCT had a sensitivity,specificity,and accuracy of 77.1％ (27/35),80.0％ (12/15) and 78.0％ (39/50) for diagnosing malignant IPMN,respectively;which in MRCP were 77.1％ (27/35),86.7％ (13/15),and 80.0％ (40/50) in comparison.When MPD diameter ≥10 mm was used for diagnose malignancy,MSCT and MRCP had the sensitivity,specificity,and accuracy of 96.3％ (26/27),81.8％ (9/11),92.1％ (35/38),and 96.3％ (26/27),90.9％ (10/11),94.7％ (36/38),respectively.For thick septum ≥2 mm,MSCT and MRCP had the sensitivity,specificity,and accuracy of 4.8.6％ (17/35),93.3％ (14/15),62.0％(31/50),and 51.4％ (18/35),93.3％ (14/15),64.0％ (32/50),respectively.Out of 50 cases,calcifications were detected on MSCT in 6 patients,and 5 of them were pathologically diagnosed as malignant IPMN.MRCP failed to identify calcifications in any of these lesions.For MSCT,the AUC of MPD diameter ≥ 10 mm,mural nodules and thick septum ≥ 2 mm were 0.973 (P =0.000),0.825 (P =0.002) and 0.704(P =0.051),respectively.For MRCP,the AUC of the three factors above were 0.976(P =0.000),0.825(P =0.002),0.722 (P =0.034),respectively.For the predicting of IPMN malignancy,MSCT had an overall sensitivity,specificity,and accuracy of 94.3％ (33/35),73.3％ (11/15) and 88.0％ (44/50),respectively;in comparison,MRCP had values of 94.3％ (33/35),80.0％ (12/15) and 90.0％ (45/50),respectively.Conclusions Presence of mural nodules,MPD ≥10 mm and thick septum ≥2 mm on MSCT combined with 2D curved reconstruction or MRCP have a high value for predicting the malignancy of IPMN.The values of MSCT and MRCP were basically consistent in the differentiation of benign and malignant IPMN.MSCT can be used as the preferred examination for diagnosing IPMN in the primary hospitals without MR equipment.

Objective:To investigate the clinical value of endoscopic ultrasound elastography versus contrast-enhanced computed tomography in the risk stratification of gastrointestinal stromal tumors (GISTs). Methods:Clinical and imaging data were obtained from 77 patients who were confirmed to have GISTs and underwent endoscopic or surgical treatment at Wenzhou Central Hospital between May 2019 and April 2021. Endoscopic ultrasound elastography based on a five-point scoring system and hypotonic gastrointestinal contrast-enhanced computed tomography were performed for preoperative risk stratification of GISTs. The two techniques were compared in terms of the accuracy of preoperative risk stratification of GISTs. The imaging features of the two techniques were summarized.Results:According to the postoperative pathological results, 13 patients were at high risk, 13 patients were at medium risk, 35 patients were at low risk, and 16 patients were at extremely low risk. These patients were divided into two groups according to postoperative pathological results: a low-risk group (low risk + extremely low risk) and a medium- and high-risk group (high + medium risk). In the low-risk group ( n = 51), 42 patients were identified by endoscopic ultrasound elastography to have low-risk GISTs and were recommended to receive endoscopic treatment, while the rest 9 patients were identified to have medium-risk GISTs. Contrast-enhanced computed tomography findings revealed that 30 patients had low-risk GISTs and were recommended to receive endoscopic treatment, and 21 patients had medium-risk GISTs. In the medium- and high-risk group ( n = 26), 4 patients were identified by endoscopic ultrasound elastography to have low-risk GISTs, and 22 patients had medium- or high-risk GISTs. Contrast-enhanced computed tomography findings revealed that 9 patients were identified to have low-risk GISTs, and 17 patients had medium- or high-risk GISTs. Endoscopic ultrasound elastography yielded an overall diagnostic accuracy of 83.11% (64/77), while contrast-enhanced computed tomography had an overall diagnostic accuracy of 61.04% (47/77). Endoscopic ultrasound elastography outperformed contrast-enhanced computed tomography in accurate risk stratification of GISTs ( χ2 = 4.66, P < 0.05). In terms of predicting high-risk GISTs, endoscopic ultrasound elastography had a sensitivity of 84.62% and a specificity of 82.35%, both were higher than those of contrast-enhanced computed tomography (sensitivity: 65.38%; specificity: 58.82%), but the differences in sensitivity and specificity between the two techniques were not significant (sensitivity: Fisher's exact test P = 0.590, specificity: χ2 = 0.93, P > 0.05). Conclusion:Endoscopic ultrasound elastography appears to have a better overall diagnostic accuracy in the risk stratification of GISTs compared with contrast-enhanced computed tomography. The combined use of these two techniques may offer a better comprehensive understanding of the perilesional structure and organ involvements and distant metastasis than a single technique, thereby providing a reliable reference for the choice of treatment for GISTs.