Objective To investigate the expressions of peroxisome proliferator activated receptor-γ (PPAR-γ) and β-catenin in 5-aminosalicylic acid （ASA) intervened colitis carcinogenesis mouse model induced by azoxymethane (AOM) and dextran sulfate sodium (DSS).Methods Thirtysix BALB/c mice were evenly divided into control group,model group,and intervention group.For model group and intervention group,mice were intraperitoneally injected with AOM (10 mg/kg) one day before experiment,then drank 4％ DSS solution freely for one week and followed with common drinking water for another two weeks.Taking 4％ DSS solution and common drinking water repeated for three cycles.For intervention group,5-ASA (150 mg/kg) was given from three days before experiment to the end of research.For control group,mice were intraperitoneally injected with 0.9％NaCl solation and then given common drinking water for nine weeks.The symptoms of the disease were monitored in mice and pathological changes of tissues were evaluated at the end of first week and ninth week.At the end of the ninth week,the expressions of PPAR-γ,β-catenin protein and PPAR-γat mRNA level in colon tissue were detected.The data were analyzed by t test.Results The colitis disease activity index (DAI) index of intervention group was 1.81 ±0.59 after drinking DSS solution for one week and the number of tumor was 4.11 ± 1.05 at the end of the ninth week,both were significantly lower than those of model group (2.47 ± 0.53 and 9.71±2.29 respectively,t=2.88 and 6.55; both P＜0.01).The expression of PPAR-γ at protein level (2.11±1.36) and mRNA level (1.45±0.10) in colon tissue of intervention group significantly increased compared with those of model group (0.43±0.53 and 0.57±0.08 respectively,t=3.07 and 18.99,both P＜0.01).There was no significant difference of β-catenin expression among groups (P＞0.05).Conclusions 5-ASA can efficiently improve the inflammatory reaction and tumor load in AOM and DSS induced colitis carcinogenesis mouse model,and at the same time can promote the expression of PPAR-γ in colon.However,there was no significant influence on the expression of β-catenin.

To review the clinical data of 13 patients with benign stenosis in deep small intestine treated by balloon-assisted enteroscopy from September 2017 to December 2019, and to evaluate the stenosis characteristics, endoscopic treatment effects and its safety in different lesions. The results showed that there were 6 cases of Crohn disease (CD), 4 cases of cryptogenic multifocal ulcerative stenosing enteritis (CMUSE) and 3 cases of small bowel stenosis with unknown etiology. A total of 38 stenoses were found after 17 enteroscopic treatments, including 35 web-like stenoses and 3 columnar stenoses. Thirteen stenoses were found in 6 patients with CD, including 4 single stenosis, 1 case of 3 stenoses and 1 case of 6 stenoses. Twenty-one stenoses were found in 4 patients with CMUSE and they were all web-like stenosis. A total of 18 times of balloon dilatation and 10 times of IT knife incision were performed. The technical success rate was 88.2% (15/17), and the clinical effective rate was 76.9% (10/13). The follow-up time was 3-28 months, and one patient underwent surgical treatment. There was 1 case of delayed hemorrhage and 3 cases of delayed perforation after operation. They were all improved by medical treatment. These results indicated that treatment of benign stenosis in deep small intestine by enteroscopy is technically feasible and can improve the symptoms of patients in a short time.

Objective:To evaluate the influence on the results and safety of double-balloon enteroscopy (DBE) at different combination time.Methods:Patients who received combined DBE procedures in Nanjing Drum Tower Hospital from April 2019 to August 2020 were divided into the one-day combination group and the non-one-day combination group. The complete enteroscopy rate, time of anterograde approach, time of retrograde approach, total time of combined approach, adverse events, hospital stay and cost were compared.Results:Among 119 patients who received DBE, 23 patients were excluded due to small intestinal stenosis. The complete enteroscopy rate was 92.9% (39/42) in the one-day group and 74.1% (40/54) in the non-one-day group, showing significant difference ( χ2=4.390, P=0.036). There were significant differences in the time of retrograde approach (35.59±23.29 min VS 55.10±19.04 min, t=-4.080, P<0.001), total time of combined approach (89.10±27.82 min VS 114.20±24.55 min, t=-4.254, P<0.001), hospital stay (9.24±3.76 d VS 11.76±4.41 d, t=-2.599, P=0.011) between the two groups. There were no significant differences in the time of anterograde approach, hospital cost or adverse events between the two groups. Conclusion:Combined DBE on one day yields a higher complete enteroscopy rate, less examination time and less hospital stay, which is worth of clinical application.

Objective:To evaluate the value of non-injection mucosal resection for Paris type 0-Ⅰ colon polyps with a long diameter less than 2 cm.Methods:At the Department of Gastroenterology, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, patients with type 0-Ⅰcolonic polyps of a long diameter less than 2 cm who underwent non-submucosal injection resection from January 2019 to December 2019 were enrolled as the non-injection group, and those who received endoscopic mucosal resection (EMR) in the same period were enrolled as the control (EMR group). The differences in complete resection rate, operation time, complication incidence and 1-year follow-up polyp detection rate between the two groups were compared.Results:A total of 373 patients were treated with non-injection mucosal resection and 743 patients with conventional EMR. There was no significant difference in gender [68.6% (256/373) VS 64.6% (480/743) for male, χ2=1.796], age (56.2±11.8 years VS 57.4±11.2 years, t=-1.984), number of polyps (1.5±0.9 VS 1.4±0.8, t=1.776), polyp distribution [48.0% (269/561) VS 34.6% (362/1 045) in right colon, χ2=3.364], lesion diameter less than 1 cm [80.0% (449/561) VS 76.9% (804/1 045), χ2=2.043] between the two groups ( P>0.05). The operation time in the non-injection group was 2.82±1.70 min, which was shorter than that in the EMR group (4.94±2.54 min) with significant difference ( t=-16.489, P<0.001). The number of metal clips used in the non-injection group was 0.90±0.68, which was less than that in the EMR group (1.30±0.73, t=-8.971, P<0.001). The en bloc resection rates of lesions in non-injection group and EMR group were both 100.0%. The complete resection rate of non-injection group was 97.3% (546/561), which was not significantly different from that of EMR group [98.1% (1 025/1 045), χ2=0.749, P=0.387]. There was no significant difference in the incidences of delayed bleeding in the two groups [0.0% (0/373) VS 0.8% (6/743), P=0.187]. No intraoperative or delayed perforation in either group occurred. There was no significant difference in the incidence of electrocoagulation syndrome between the two groups [0.8% (3/373) VS 0.7% (5/743), P=0.534]. A total of 63 patients in the non-injection group underwent colonoscopy review within the set period, and the polyp detection rate was 41.2% (26/63). A total of 178 patients in the EMR group also underwent colonoscopy review, and the polyp detection rate was 53.9% (96/178). There was no significant difference in the polyp detection rate between the two groups ( χ2=2.985, P>0.05). Conclusion:Non-submucosal injection resection is safe and effective for Paris type 0-Ⅰ colon polyps with a long diameter less than 2 cm, which can significantly shorten the operation time and is worth of clinical promotion.

Objective:To analyze the clinicopathological features of histological mixed-type early gastric cancer and to compare the endoscopic pathological features of dominant proportions.Methods:Clinical data of 43 patients with histological mixed-type early gastric cancer who underwent endoscopic submucosal dissection (ESD) at the Department of Gastroenterology, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School from January 2015 to December 2020 were retrospectively analyzed. The endoscopic characteristics, coincidence rate of preoperative diagnosis and postoperative pathology of the patients were analyzed. The endoscopic pathological findings of differentiation dominant group and undifferentiation dominant group were compared.Results:Histological mixed-type early gastric cancer was more common in patients over 60 years old (55.81%, 24/43) , male (65.12%, 28/43), and Helicobacter pylori ( HP) infection (69.77%, 30/43). Most lesions were found in atrophic background (79.07%, 34/43), and lower part of stomach (65.12%, 28/43). Redness or mixed redness was the main color (76.74%, 33/43), and 0-Ⅱc was the main type in lesion morphology (58.14%, 25/43). Characteristics of both differentiated and undifferentiated carcinoma could be observed under magnifying endoscopy. Only 16.28% (7/43) of the patients were diagnosed as having histological mixed-type carcinoma by biopsy. Postoperative pathology showed that there were 33 cases in differentiation dominant group and 10 cases in undifferentiation dominant group. There were 15 (34.88%) patients with deep submucosal infiltration, and 3 (6.98%) patients with positive lymphatic vessels. Differentiation dominant group had clearer demarcation line under endoscopy [78.79% (26/33) VS 4/10, χ2=7.753, P=0.012]. There was no significant difference between the two groups in gender, HP infection, background mucosa, lesion location, endoscopic morphology, lesion long diameter, color, or microscopic and microvascular manifestations under magnifying endoscopy ( P>0.05). Tub2+por was the most common pathological type in differentiation dominant group (78.79%, 26/33), and sig+tub2 was the dominant combination in undifferentiation dominant group (6/10). Endoscopic diagnosis of differentiated primary carcinoma was highly sensitive (93.94%, 31/33), and highly specific for undifferentiated primary carcinoma (94.28%, 33/35). Conclusion:Histological mixed-type early gastric cancer can be diagnosed qualitatively by endoscopy. It is difficult to accurately judge the differentiation advantage and the invasion depth before the operation, which is prone to postoperative pathological upgrading. Therefore, the indications should be strictly considered for ESD treatment for mixed-type early gastric cancer.

To evaluate the effectiveness and safety of 8-ring assisted traction in endoscopic submucosal dissection (ESD), a total of 13 patients with 15 gastric lesions who underwent 8-ring traction-assisted ESD in Nanjing Drum Tower Hospital from July 2021 to January 2022 were included in the retrospective cohort study. All patients successfully completed the operation. The median procedure time was 56 min, and the dissected area per unit time was 0.20±0.02 cm 2/min. The en bloc resection rate, the complete resection rate and the curative resection rate were 93.3% (14/15), 80.0% (12/15) and 80.0% (12/15), respectively. There were no ESD-related complications, such as delayed bleeding or intraperative and postoperative perforation. No deaths occurred. As a novel internal traction technology, 8-ring traction method is simple to operate, providing a good field of vision during ESD to improve the dissection efficiency and reduce complications, which is worthy of further clinical research and promotion.

Objective:To evaluate the efficacy and outcomes of early removal of lumen-apposing metal stent (LAMS) in the treatment of pancreatic wall-off necrosis (WON).Methods:A retrospective analysis was performed on 51 patients with WON who underwent endoscopic ultrasound (EUS)-guided transluminal drainage (ETD) and direct endoscopic necrosectomy (DEN) using LAMS at Nanjing Drum Tower Hospital from January 2018 to December 2022. Patients were divided into the early removal group (within two weeks, n=24) and the traditional removal group (after two weeks, n=27) based on the timing of LAMS removal. The short-term effects, safety and long-term outcomes of WON were compared between the two groups. Results:The technical success rate of LAMS placement in 51 patients reached 100%, and all patients underwent ETD and DEN. The median number of necrosectomy sessions in the early removal group was significantly lower than in the traditional removal group, 2.0 sessions vs 3.0 sessions and the difference was statistically significant ( P<0.05). Postoperatively, 15.7% of patients required percutaneous catheter drainage (PCD) and 5.9% required surgery, with no significant difference between the two groups. The clinical success rate and mortality rate in the early removal group were 79.2% and 8.3%, respectively, compared to 81.5% and 3.7% in the traditional removal group, with no statistically significant difference. In terms of safety, the early removal group exhibited a significantly lower rate of adverse events during stent retention with statistically significant difference (12.5% vs 37.0%, P<0.05) compared to the traditional removal group. A total of 46 patients were followed up for six months. In the early removal group, the rates of disease recurrence, need for endoscopic reintervention and occurrence of long-term complications were 20.0%, 10.0% and 20.0%, respectively. These rates did not show a significant increase compared to the traditional removal group, which were 7.7%, 3.8% and 38.5%, respectively, without significant differences between the groups. Conclusions:In the treatment of WON, early removal of LAMS is safe and effective to a certain extent. In comparison to the traditional practice of removing LAMS after two weeks, early removal does not reduce clinical success rates, nor does it increase the rates of disease-related mortality, recurrence, or long-term complications. On the contrary, it may reduce the occurrence of adverse events during stent retention and decrease the number of necrosectomy procedures subsequently.

Objective:To compare the efficacy of endoscopic submucosal dissection (ESD) and modified-endoscopic mucosal resection (M-EMR) for G1 rectal neuroendocrine tumors (RNETs) .Methods:Data of 121 patients with pathologically confirmed G1 RNETs treated with ESD ( n=105) or M-EMR ( n=16) in Nanjing Drum Tower Hospital from January 2017 to September 2020 were retrospectively analyzed. The complete resection rate, complication incidence, hospital stay, treatment cost and other indicators of the two groups were compared by using inverse probability of treatment weighting (IPTW). Results:There were significant differences in tumor number ( χ2=8.76, P=0.003), tumor invasion depth ( χ2=6.96, P=0.008), utilization of metal clips [82.9% (87/105) VS 93.8% (15/16), χ2=8.78, P=0.003], number of metal clips ( χ2=8.41, P=0.016), hemostasis using hot clamp [78.1% (82/105) VS 18.7% (3/16), χ2=20.64, P<0.001], traction procedure [2.9% (3/105) VS 18.7% (3/16), χ2=4.45, P=0.035] and treatment cost (17 568.6 ± 8 911.0 yuan VS 8 120.8±1 528.2 yuan, t=3.65, P<0.001) between the ESD group and the M-EMR group. After verifying the stability of the results using IPTW sensitivity analysis, there was still significant difference in the treatment cost ( t=2.07, P<0.001). Conclusion:Both ESD and M-EMR demonstrate comparable efficacy in treating G1 RNETs; however, M-EMR exhibites lower treatment costs.

Objective:To assess the safety and efficacy of single metal clip traction-assisted endoscopic submucosal dissection (ESD) for the treatment of duodenal lesions.Methods:Data of 45 patients with duodenal lesions who underwent ESD in Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School between April 2021 and October 2022 were retrospectively recruited. Among them, 19 patients received single metal clip traction- assisted ESD while 26 patients received traditional ESD. The incidence of complications, dissection speed, en bloc resection rate and R0 resection rate of the two groups were mainly observed. Secondary observation indexes included specimen longer diameter, shorter diameter and area.Results:All 45 procedures were successfully completed, with the procedure time of 44.0 (27.0, 67.0) min for the single metal clip traction- assisted ESD group and 34.0 (24.0, 43.5) min for the traditional ESD group ( Z=-1.678, P=0.093). In the single metal clip traction-assisted ESD group, 2 cases (10.5%) had complications, including 1 intraoperative perforation and 1 postoperative bleeding (approximately 20 mL). There were three cases (11.5%) of complications in the traditional ESD group, including 1 case of postoperative bleeding (approximately 50 mL) and 2 cases of postoperative perforation, with no significant intergroup variation ( P=1.000). The dissection speed of the single metal clip traction-assisted ESD group was 16.0 (11.0, 25.8) mm 2/min, significantly larger than that of the traditional ESD group [5.3 (2.2, 21.1) mm 2/min, Z=-2.287, P=0.022]. The en block resection rate and R0 resection rate of the single metal clip traction-assisted ESD group were both 100.0% (19/19). Additionally, the specimen longer diameter, shorter diameter and area of the single metal clip traction-assisted ESD group were 34.0 (22.0, 45.0) mm, 25.0 (20.0, 34.0) mm, and 745.8 (380.0, 1 342.4) mm 2, respectively, significantly larger than those of the traditional ESD group of 20.0 (12.8, 30.3) mm ( Z=-3.119, P=0.002), 14.0 (8.8, 21.3) mm ( Z=-3.417, P=0.001), 190.4 (84.0, 498.7) mm 2 ( Z=-3.275, P=0.001). Conclusion:Single metal clip traction is safe and effective for duodenal ESD, demonstrating a notable improvement in the dissection speed, especially suitable for large duodenal lesions.

Objective:To evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for circular superficial esophageal cancer.Methods:A retrospective analysis was conducted on 74 consecutive cases of circular superficial esophageal squamous cell carcinoma treated with ESD at Nanjing Drum Tower Hospital from January 2015 to December 2019. The success rate of ESD, curative resection rate, incidence of complications, and additional treatment were mainly observed.Results:One case was transferred to surgery, and the remaining 73 cases successfully completed ESD treatment. The success rate of ESD was 98.6%. Postoperative pathology of ESD revealed that 39 cases achieved curative resection, with a curative resection rate of 53.4% (39/73). Intraoperative muscle layer injury occurred in 15 cases (20.5%), and intraoperative perforation occurred in 1 case (1.4%). Two cases (2.7%) experienced delayed bleeding, and one case (1.4%) experienced delayed perforation. Eleven cases were lost to follow-up, and the remaining 62 cases received follow-up for 36.4±19.0 months. Among the follow-up cases, 12 underwent additional surgery and 5 cases additional chemotherapy and radiotherapy. Among the 57 patients with follow-up data who did not underwent surgery, 49 developed esophageal stenosis after ESD, with an incidence rate of 86.0%.Conclusion:ESD for circular superficial esophageal cancer is generally safe, but it is prone to muscle layer injury during the operation, with a low curative resection rate, a high incidence of postoperative esophageal stenosis, and a high proportion of additional surgical procedures.