Objective:To investigate the predictive value of computed tomography(CT) based radiomics model for the prognosis of patients with pancreatic ductal adenocarcinoma(PDAC).Methods:The retrospective cohort study was conducted. The clinicopathological data of 206 PDAC patients who were admitted to Zhongshan Hospital of Fudan University from August 2018 to December 2020 were collected. There were 115 males and 91 females, aged (64±9)years. All 206 pati-ents underwent enhanced CT examination. Based on radom number table, the 206 patients were randomly divided into a training set of 165 cases and a validation set of 41 cases with a ratio of 4∶1. The training set was used to construct the prediction model, and the test set was used to validate the performance of the prediction model. Observation indicators: (1) follow-up; (2) analysis of prognostic factors of PDAC patients in the training set; (3) construction and evaluation of prediction model for prognosis of PDAC patients. Comparison of measurement data with normal distribution between groups was conducted using the t test. Comparison of measurement data with skewed distribution between groups was conducted using the Wilcoxon W test. Comparison of count data between groups was conducted using the chi-square test or corrected chi-square test. The Kaplan-Meier method was used to calculate the survival rate and Log-rank test was used for survival analysis. Univariate and multivariate analyses were conducted using the COX regression model. The PyCharm software was used for the least absolute shrinkage and selection operator method (LASSO)-COX regression analysis. The receiver operating characteristic curve was plotted to evaluate the performance of radiomics model. Results:(1)Follow-up. Of the 206 patients,205 cases were followed up for 17.1(range, 12.0?40.1)months. The postoperative 1-, 2-, 3-year survival rates were 80.10%, 29.61% and 4.85%. (2) Analysis of prognostic factors for PDAC patients in the training dataset. Results of multivariate analysis showed that pathological N stage was an independent influencing factor for prognosis of PDAC patients in the training set ( hazard ratio=1.476, 95% confidence interval as 1.054?2.067, P<0.05). (3) Construction and evaluation of prediction model for prognosis of PDAC patients. A total of 1 595 radiomics features were finally extracted from the 206 patients. By intra-group feature selection and dimensionality reduction using LASSO-COX regression model, 10 radiomics features were obtained. Combined with 10 radiomics features and 11 clinical features, using the LASSO-COX regression analysis, 15 features were finally extracted to construct the CT based radiomics model for predicting prognosis of PDAC. The areas under receiver operating characteristic curve of the prediction model in predicting 2-year and 3-year overall survival rates of PDAC patients in the training set were 0.834 (95% confidence interval as 0.777?0.891) and 0.883 (95% confidence interval as 0.834?0.932), respectively. The area under curve of the prediction model for patients in the validation set was 0.606 (95% confidence interval as 0.456?0.756) and 0.625 (95% confidence interval as 0.477?0.773). Conclusion:The prediction model constructed on CT based radiomics features and clinical features for predicting the prognosis of PDAC patients shows a promising prediction efficiency.

Objective:To investigate the predictive value of computed tomography(CT) based radiomics model for the prognosis of patients with pancreatic ductal adenocarcinoma(PDAC).Methods:The retrospective cohort study was conducted. The clinicopathological data of 206 PDAC patients who were admitted to Zhongshan Hospital of Fudan University from August 2018 to December 2020 were collected. There were 115 males and 91 females, aged (64±9)years. All 206 pati-ents underwent enhanced CT examination. Based on radom number table, the 206 patients were randomly divided into a training set of 165 cases and a validation set of 41 cases with a ratio of 4∶1. The training set was used to construct the prediction model, and the test set was used to validate the performance of the prediction model. Observation indicators: (1) follow-up; (2) analysis of prognostic factors of PDAC patients in the training set; (3) construction and evaluation of prediction model for prognosis of PDAC patients. Comparison of measurement data with normal distribution between groups was conducted using the t test. Comparison of measurement data with skewed distribution between groups was conducted using the Wilcoxon W test. Comparison of count data between groups was conducted using the chi-square test or corrected chi-square test. The Kaplan-Meier method was used to calculate the survival rate and Log-rank test was used for survival analysis. Univariate and multivariate analyses were conducted using the COX regression model. The PyCharm software was used for the least absolute shrinkage and selection operator method (LASSO)-COX regression analysis. The receiver operating characteristic curve was plotted to evaluate the performance of radiomics model. Results:(1)Follow-up. Of the 206 patients,205 cases were followed up for 17.1(range, 12.0?40.1)months. The postoperative 1-, 2-, 3-year survival rates were 80.10%, 29.61% and 4.85%. (2) Analysis of prognostic factors for PDAC patients in the training dataset. Results of multivariate analysis showed that pathological N stage was an independent influencing factor for prognosis of PDAC patients in the training set ( hazard ratio=1.476, 95% confidence interval as 1.054?2.067, P<0.05). (3) Construction and evaluation of prediction model for prognosis of PDAC patients. A total of 1 595 radiomics features were finally extracted from the 206 patients. By intra-group feature selection and dimensionality reduction using LASSO-COX regression model, 10 radiomics features were obtained. Combined with 10 radiomics features and 11 clinical features, using the LASSO-COX regression analysis, 15 features were finally extracted to construct the CT based radiomics model for predicting prognosis of PDAC. The areas under receiver operating characteristic curve of the prediction model in predicting 2-year and 3-year overall survival rates of PDAC patients in the training set were 0.834 (95% confidence interval as 0.777?0.891) and 0.883 (95% confidence interval as 0.834?0.932), respectively. The area under curve of the prediction model for patients in the validation set was 0.606 (95% confidence interval as 0.456?0.756) and 0.625 (95% confidence interval as 0.477?0.773). Conclusion:The prediction model constructed on CT based radiomics features and clinical features for predicting the prognosis of PDAC patients shows a promising prediction efficiency.

Objectives:To evaluate the role of pancreas multidisciplinary team(MDT) clinic in the diagnosis of pancreatic diseases,patient compliance with MDT advice,and the impact of MDT on the postoperative survival of patients with pancreatic cancer.Methods:The study included 927 patients(554 males,373 females,aged (58.1±13.3)years (range: 15 to 89 years)) that had visited the pancreas MDT clinic of Zhongshan Hospital from May 2015 to December 2021,and 677 patients(396 males, 281 females, aged (63.6±8.9)years(range: 32 to 95 years)) who underwent radical surgery and with pathologically confirmed pancreatic adenocarcinoma from January 2012 to December 2020,of whom 79 patients had attended the pancreas MDT. The clinical and pathological data were collected and analyzed retrospectively. Diseases were classified in accordance with 2010 WHO classification of tumors of the digestive system and usual clinical practices. The Kaplan-Meier method was used for drawing the survival curve and calculating the survival rate. The univariate analysis was done by Log-rank test and the multivariate analysis was done by COX proportional hazards model. Survival rates were compared using χ 2 test. Results:Among the 927 patients that had visited the MDT clinic,233 patients(25.1%) were referred due to undetermined diagnosis. A direct diagnosis was made in 109 cases (46.8%,109/233) by the MDT clinic, of which 98 were consistent with the final diagnosis,resulting in an accuracy of 89.9%(98/109). The direct diagnosis rate in the recent years(36.6%(41/112),from June 2019 to December 2021) decreased compared to that in the previous years(56.2%(68/121),from May 2015 to May 2019),yet the accuracy in the recent years(90.2%,37/41) was basically the same as before (89.7%,61/68). The rate of compliance of the entire cohort was 71.5%(663/927), with the compliance rate in the recent two and a half years(81.4%,338/415) remarkably higher than that in the previous four years(63.4%,325/512). Patients with pancreatic cancer that attended the MDT exhibited a trend toward longer median postoperative survival than patients that did not attend the MDT,but the difference was not statistically significant(35.2 months vs.30.2 months, P>0.05). The 1-year and 3-year survival rates of patients that attended the MDT were significanly higher than patients that did not attend the MDT(88.6% vs. 78.4%, P<0.05;32.9% vs. 21.9%, P<0.05,respectively),but the 5-year survival rate was not statistically different(7.6% vs. 4.8%, P>0.05). Conclusions:The pancreas MDT clinic is an accurate and convenient way to diagnose intractable pancreatic diseases,and in the recent years the patients′ compliance rate with MDT advice has increased. Pancreatic cancer patients that have attended the MDT have higher 1-year and 3-year postoperative survival rates,but the long-term survival benefits of MDT still needs to be proved by clinical studies on a larger scale.

Objectives:To evaluate the role of pancreas multidisciplinary team(MDT) clinic in the diagnosis of pancreatic diseases,patient compliance with MDT advice,and the impact of MDT on the postoperative survival of patients with pancreatic cancer.Methods:The study included 927 patients(554 males,373 females,aged (58.1±13.3)years (range: 15 to 89 years)) that had visited the pancreas MDT clinic of Zhongshan Hospital from May 2015 to December 2021,and 677 patients(396 males, 281 females, aged (63.6±8.9)years(range: 32 to 95 years)) who underwent radical surgery and with pathologically confirmed pancreatic adenocarcinoma from January 2012 to December 2020,of whom 79 patients had attended the pancreas MDT. The clinical and pathological data were collected and analyzed retrospectively. Diseases were classified in accordance with 2010 WHO classification of tumors of the digestive system and usual clinical practices. The Kaplan-Meier method was used for drawing the survival curve and calculating the survival rate. The univariate analysis was done by Log-rank test and the multivariate analysis was done by COX proportional hazards model. Survival rates were compared using χ 2 test. Results:Among the 927 patients that had visited the MDT clinic,233 patients(25.1%) were referred due to undetermined diagnosis. A direct diagnosis was made in 109 cases (46.8%,109/233) by the MDT clinic, of which 98 were consistent with the final diagnosis,resulting in an accuracy of 89.9%(98/109). The direct diagnosis rate in the recent years(36.6%(41/112),from June 2019 to December 2021) decreased compared to that in the previous years(56.2%(68/121),from May 2015 to May 2019),yet the accuracy in the recent years(90.2%,37/41) was basically the same as before (89.7%,61/68). The rate of compliance of the entire cohort was 71.5%(663/927), with the compliance rate in the recent two and a half years(81.4%,338/415) remarkably higher than that in the previous four years(63.4%,325/512). Patients with pancreatic cancer that attended the MDT exhibited a trend toward longer median postoperative survival than patients that did not attend the MDT,but the difference was not statistically significant(35.2 months vs.30.2 months, P>0.05). The 1-year and 3-year survival rates of patients that attended the MDT were significanly higher than patients that did not attend the MDT(88.6% vs. 78.4%, P<0.05;32.9% vs. 21.9%, P<0.05,respectively),but the 5-year survival rate was not statistically different(7.6% vs. 4.8%, P>0.05). Conclusions:The pancreas MDT clinic is an accurate and convenient way to diagnose intractable pancreatic diseases,and in the recent years the patients′ compliance rate with MDT advice has increased. Pancreatic cancer patients that have attended the MDT have higher 1-year and 3-year postoperative survival rates,but the long-term survival benefits of MDT still needs to be proved by clinical studies on a larger scale.

Objective: To evaluate the role of multidisciplinary team (MDT) clinic in the diagnosis of pancreatic diseases and patient compliance with MDT advice in the current medical system. Methods: The study included 512 patients that had visited the pancreas-oriented MDT clinic of Zhongshan Hospital between May 2015 and May 2019.The clinical and pathological data were collected and analyzed retrospectively. Diseases were classified in accordance with 2010 WHO classification of tumors of the digestive system and usual clinical practices. Compliance was determined according to whether a patient received corresponding therapies or undergoing further checks or follow-ups. Results: Among the 512 patients that had visited the MDT clinic, 121 patients were referred due to undetermined diagnosis. Classified according to the final diagnosis, the rate of undetermined diagnosis in different disease categories from high to low in order was inflammatory diseases of the pancreas (75.0%, 24/32), other lesions of the pancreas (56.1%,23/41), pancreatic cystic lesions (19.1%,17/89), pancreatic carcinomas (18.3%,48/262) and pancreatic neuroendocrine neoplasms (pNEN)(10.2%,9/88). The MDT clinic made diagnosis to 68 patients directly with an accuracy of 89.7%. The rate of compliance in the entire cohort was 63.4%. The rate of compliance of patients from June 2017 to May 2019 (68.4%) was higher than that of patients from May 2015 to May 2017(59.6%). The compliance rate of patients in different disease categories from high to low in order was inflammatory diseases of the pancreas(84.4%, 27/32), pancreatic carcinomas (67.9%, 178/262), pNEN(60.2%,53/88), other lesions of the pancreas (56.1%,23/41), and pancreatic cystic lesions(49.4%, 44/89). The compliance rate of patients with different MDT advice from high to low in order was best supportive care(78.6%,22/28), antitumor approaches beyond surgery(71.6%,159/222), further tests(62.6%, 77/123), surgery(53.7%, 65/121) and follow-up(49.2%, 31/63). In patients suggested for surgery, the compliance rate of patients with carcinomas(67.4%, 33/49) was higher than patients with other kinds of neoplasms. Conclusions MDT clinic could facilitate the diagnosis of pancreatic diseases conveniently and inexpensively. The overall compliance rate of MDT clinic patients is rather low, and patients with carcinomas have a relative high rate of compliance with the suggestion of surgery.

Objective To prepare gadolinium-loaded stearic acid grafted chitooligosaccharide (COSSA-DTPA-Gd) and evaluate its micelle properties,cytotoxicity,relaxation rate in vitro,and pancreatic tumor in vivo imaging.Methods Stear ic acid grafted chitooligosaccharide (COSSA) was synthesized by acetylation reaction between stearic acid and chitooligosaccharide.Diethylenetriaminepentaacetic dianhydride (DTPA) was conjugated to the residual amino groups of COSSA,then Gd3+ was chelated to obtain the final product.The micelle properties were measured using an electron microscopy and a laser particle sizer.The MTT assay was adopted to determine cytotoxicity.The in vitro relaxation rate and in vivo imaging of pancreatic tumor were evaluated using an MR scanner.Results COSSA-DTPA-Gd could self-assemble into stable micelles in aqueous solutions with a critical micelle concentration of (5.12±0.43)μg/ml.The micelles had positive charge and exhibited roughly spherical shape with a mean diameter of (58.3± 5.7)nm.The content of Gd3+ in COSSA-DTPA-Gd was 330.31 μmol/g.The nanoprobe and Magnevist,the commercial formulation,showed similar cytotoxicity (P＞0.05).The cell survival rate within 24 h were higher than 85％.The in vitro relaxation rate of COSSA-DTPA-Gd was 8.23 mM-1 ·s-1.After intravenous injection,COSSA-DTPA-Gd showed a better positive contrast-enhancing effect for pancreatic tumor than Magnevist.The MR images at the tumor periphery was rapidly enhanced,while a slow increase in image quality was observed in tumor core.Conclusion The prepared COSSA-DTPA-Gd can be used for efficient MR imaging of pancreatic tumor.

Objective To evaluate transoral Orvil EEA stapler (OrVil) procedure in laparoscopic total gastrectomy for cardiac carcinoma compared with conventional anvil head method (purse-string suture).Methods From May 2014 to December 2014 20 cases were included into OrVil group,and 25 cases into purse-string suture group.Results The two groups had similar mean numbers of dissected lymph nodes [(25 ± 3) vs.(24 ± 4),t =1.067,P =0.292],the mean time of operation,intraoperative blood loss,and postoperative complications (5 vs.6,P =0.938).The length of incision was significantly shorter [(5 ±1) cm vs.(11 ± 2) cm,t =-10.724,P ＜ 0.0l] and the esophagojejunostomy time was significantly less [(28 ± 4) min vs.(39 ± 5) min,t =-7.996,P ＜ 0.01] with the use of OrVil.The time to first flatus and postoperative hospital stay were (3.7 ± 0.9) d vs.(4.4 ± 1.0) d,t =-2.485,P =0.017 and (13 ± 5) d vs.(16 ±4) d,t =-2.184,P =0.035.Conclusions OrVil is a technically safe and feasible surgical procedure for esophagojejunostomy in laparoscopy assisted total gastrectomy in the treatment of cardiac carcinoma.

Objective To explore the effect on image quality and scanning time by changing parameters and using different scan-ning technique for the clinical application of axial FLAIR pulse sequence.Methods Seven different sets of parameters of T2-FLAIR Pulse Sequences were performed on thirty patients at a 3.0 T MR scanner.Group A was scanned with a routine sequence for refer-ence.Group B,reducing the matrix to 128.Group C,increasing the turbo factor parameter to 24.Group D,setting the contatena-tion to 1.Group E setting the Accel.factor PE to 4.Group F,using a BLADE-FLAIR sequence.Group G,using a HASTE-FLAIR sequence.The SNRs of all images were statistically analyzed by ANOVA among 7 sequences.The image quality of all images was statistically analyzed by Kruskal-Wallis test among 7 sequences.Results The SNR of seven groups of images were 54.69 ±8.12, 1 57.57±25.61,44.56±7.37,38.48 ± 9.32,44.1 9 ±8.79,45.60 ± 6.92,105.20 ± 18.25,respectively(F = 266.368,P =0.000). The scores of image quality were 3.87±0.09,2.50±0.12,3.72±0.1 6,3.10±0.10,1.88±0.10,3.92±0.07,2.08±0.10,re-spectively and the differences among groups were statistically significant(χ2 =1 93.361,P =0.000).Conclusion Suitable turto factor and BLADE technique can be the best option for FLAIR sequence in the head.HASTE-FLAIR sequence can act as the secondary op-tion for the uncooperative patients.

Objective:To compare the value of respiratory-triggered diffusion-weighted imaging with fat suppression(RTIR-DWI)and common breath-hold DWI(BH-DWI)for the differential diagnosis of pancreatic cancer and mass-like pancreatitis. Methods:A total of 30 cases of pancreatic cancer and 17 cases of mass-like pancreatitis,which were confirmed by surgical pa-thology,underwent DWI at 3.0T before operation.DWI based on SE-EPI sequence,of which b value was 600 s/mm2 ,included BH-DWI and RTIR-DWI.Apparent diffusion coefficient(ADC)value of pancreatic cancer and mass-like pancreatitis were statis-tically analyzed and compared.Receiver operating characteristic(ROC)curve was used to analyze and compare the effect of two DWI sequences in the differential diagnosis of pancreatic cancer and mass-like pancreatitis.Results:On BH-DWI,ADC value did not have significant difference between pancreatic cancer and mass-like pancreatitis(P >0.05).On RTIR-DWI,ADC value had significant difference between pancreatic cancer and mass-like pancreatitis(P <0.01).On RTIR-DWI,the sensitivity,speci-ficity,positive predictive value and negative predictive value were 86.7%,88.9%,96.3% and 66.7%,respectively,when ADC≥1.33×10-3 mm2/s was used as a cutoff for the differential diagnosis of pancreatic cancer from mass-like pancreatitis.On BH-DWI,the sensitivity,specificity,positive predictive value and negative predictive value was 73.3%,88.9%,95.7% and 50.0%,respectively,when ADC≥ 1.45 × 10-3 mm2/s was used as a cutoff for the differential diagnosis of pancreatic cancer from mass-like pancreatitis.Conclusions:Compared to BH-DWI,RTIR-DWI may be more conducive to the diagnosis and differentiation of pancreatic cancer and mass-like pancreatitis.

Objective To investigate the diagnostic value of different DWI sequences for pancreatic cancer on a 3.0 T MR scanner.Methods Different DWI acquisitions based on SE-EPI sequence were preoperatively performed in 30 patients with pancreatic cancer proven by histopathology on a 3.0 T MR scanner.The patients included 17 males and 13 females.Their age ranged from 39 to 72 years with mean of (57.6 ± 14.9) years.The b values were 0 and 600 s/mm2 and the following sequences were included:breath-hold DWI with MPG pulses in X,Y,Z direction (BH600ALL),breath-hold DWI with MPG pulses in Z direction(BH600SI),respiratory-triggered DWI with MPG pulses in X,Y,Z direction (TRIG600ALL),respiratory-triggered DWI with MPG pulses in X,Y,Z direction and inversion recovery for fat saturation (TRIG600ALL+FS) and free-breathing DWI with MPG pulses in X,Y,Z direction and inversion recovery for fat saturation (FB600ALL+ FS).C,CNR and ADC of pancreatic cancer were caculated and compared among different DWI sequences by statistic mathed.Results CNR (F =11.444,P ＜ 0.001) and C (F =5.447,P ＜ 0.05) of pancreatic cancer displayed noticeably statistical difference among BH600ALL、BH600SI、TRIG600ALL、TRIG600ALL + FS and FB600ALL + FS DWI sequences by ANOVA.Among those five different DWI sequences,the highest CRN of pancreatic cancer was observed in TRIG600ALL and TRIG600ALL + FS(the values were 16.45 ± 10.37 and 13.38 ± 9.10 respectively),while the highest C of pancreatic cancer was noticed in TRIG600ALL + FS (0.39 ±0.15).ADC of pancreatic cancer had no statistical difference among BH600ALL,BH600SI,TRIG600ALL,TRIG600ALL + FS and FB600ALL + FS DWI sequences by Kruskal-Wallis test.For BH600ALL and BH600SI,there were no statistical difference among ADC of pancreatic cancer,adjacent pancreatic tissue and distal pancreatitis by ANOVA.While for all TRIG600ALL,TRIG600ALL + FS and FB600ALL + FS,there were statistical difference among ADC of pancreatic cancer,adjacent pancreatic tissue and distal pancreatitis by ANOVA (F values were 5.353,15.976 and 14.556 respectively,P ＜ 0.05).ADC of pancreatic cancer was statistically lower than that of adjacent pancreatic tissue and distal pancrcatitis on all TRIG600ALL,TRIG600ALL + FS and FB600ALL +FS (P ＜ 0.05).Conelusion Compared to other four DWI sequences,TRIG600ALL + FS had higher C and CNR in pancreatic cancer,and measurement of ADC value was helpful to disclose the histopathological state in pancreatic cancer,adjacent pancreatic tissue and distal pancreatitis.