Recently,the interest in a new surgical procedure named natural orifice transluminal endoscopic surgery has blossomed worldwidely.During these several years,quite a number of natural orifice transluminal endoscopic surgery experiments have been carried out on porcine models and even on humans,including transvaginal cholecystectomies,transgastric appendectomies,transvaginal appendectomies,transvesical peritoneoscopies,etc.This review article aims to discuss the current research status and the challenges of orifice transluminal endoscopic surgery.

Pancreatic cancer is a frequent malignant tumor in digestive tract with extremely poor prognosis,characterized by difficult early diagnosis,high malignancy,poor resective,limited response to chemotherapy and radiotherapy and an intense fibrotic reaction known as tumor desmoplasia.Pancreatic stellate cells play an important role in this reaction and can stimulate pancreatic cancer cells proliferation,invasion and metastasis through the interaction with pancreatic cancer cells.This review describes the role of pancreatic stellate cells in the process of pancreatic cancer progression.

Early diagnosis and treatment can improve the outcomes of patients with gastrointestinal neoplasms. Although digestive endoscopy is considered as a best method to diagnose gastrointestinal neoplasms,some early stage,flat-type neoplasms may be overlooked by routine endoscopy. In recent years,endoscopic autofluorescence imaging( AFI)as a new technique, has been widely applied in clinical practice for enhancing the endoscopic diagnostic accuracy of gastrointestinal neoplasms,especially for early stage,flat-type neoplasms. This article reviewed the clinical application of AFI for diagnosis of gastrointestinal neoplasms.

Objective To evaluate the effect of colonoscopy with a transparent hood on the adenoma detection rate.Methods A prospective randomized controlled trial was performed.A total of 376 patients,who underwent colonoscopy for screening colorectal polyps,were randomly allocated to 2 groups:transparent hood group (TH group,n =190) and conventional colonoscopy group (CC group,n =186).Only one endoscopist performed all the colonoscopy examinations,recorded the withdrawal time,bowel preparation status,the number,shape,location,size of adenoma when withdrawing the endoscope.All the adenoma were removed under the colonoscopy.The pathological results were recorded,and the data and relative factors were analysed.Results A total of 317 adenomas were detected in 175 patients:172 adenomas in 99 patients of TH group,145 adenomas in 76 patients of CC group.Total ADR was 46.54％.ADR of TH group was 52.11％ and ADR of CC group was 40.86％ (P =0.029).A total of 40 adenomas were found behind the fold,32 in TH group and 8 in CC group(P ＜ 0.01).In cecum and transverse colon,there were more adenomas in TH group than in CC group.In cecum,there were 23 adenomas found in TH group,6 adenomas in CC group(P ＜0.05).In transverse colon,there were 46 adenomas in TH group,25 adenomas in CC group (P ＜ 0.05).In descending colon and rectum,there were more adenomas in CC group than in TH group.In descending colon,there were 16 adenomas TH group,and 30 adenomas in CC group.In rectum,there were 14 adenomas in TH group,24 adenomas in CC group(P ＜0.05).There was no significant difference in size or shape of adenomas found between two groups.Conclusion Colonoscopy with transparent hood for screening can increase the adenoma detection rate,especially the adenoma behind the fold.

Background:Colonoscopy is considered as a standard method for detecting various kinds of colorectal polyps. However,conventional colonoscopy( CC)still has the chance to miss some lesions. Literatures have already reported that transparent hood assisted colonoscopy( THAC)can improve the detection of colorectal polyps. However,the effect of black hood assisted colonoscopy( BHAC)on detection of colorectal polyps is still unclear. Aims:To evaluate the effect of BHAC on detection of colorectal polyps. Methods:A total of 1 076 patients underwent CC and BHAC from Sept. 2014 to April 2015 at Huadong Hospital Affiliated to Fudan University were enrolled in this prospective randomized controlled study. Baseline characteristics,cecal intubation time,withdrawal time,number of polyps,detection rate of polyps,location, size,morphology and pathological diagnosis of polyps between two groups were compared. Results:Compared with CC group,cecal intubation time was significantly shorter in BHAC group than in CC group[(6. 31 ± 3. 51)min vs.(7. 05 ± 4. 15)min,P=0. 002]. No significant differences in withdrawal time and rate of cecal intubation were found between two groups(P>0. 05). Detection rate of polyps was significantly higher in BHAC group than in CC group(65. 4% vs. 48. 7%,P=0. 004). No significant differences in size,morphology of polyps were found between two groups(P>0. 05). Conclusions:Compared with CC,BHAC could significantly improve the detection of colorectal polyps,and shorten cecal intubation time.

Objective To determine risk factors for the miss rate of colorectal adenomas during colonoscopy.Methods A total of 981 patients,diagnosed as having at least one polyp in colonoscopy,received a second colonoscopy in 6 months from November 2012 to March 2016.All polyps were removed in the second colonoscopy.Bio-information of patients such as sex,age,surveillance interval and features of polyps such as number,size,shape,location,pathology,withdrawal time,bowel preparation was retrospectively analyzed.Factors associated with the miss rates in these patients were analyzed with Chisquare and was also analyzed with Logistic regression model for multiple factors.Results A total of 981 patients were selected according to the inclusion and exclusion criteria,including 604 males and 377 females.Miss rates of males and females were 38.9％ (235/604) and 27.9％ (105/377) (P＜0.01)respectively.Age ranged from 25 to 87 years with mean age being 61.0±9.7 years.Miss rates of senior patients ＜65 and ≥65 years were 31.5％(195/619) and 40.1％(145/362) respectively (P＜0.01).A total of 1 728 adenomas were found in first colonoscopy.A total of 2 267 adenomas were found in the second colonoscopy.The adenoma miss rate was 23.8％ (539/2 267).The miss rate of adenoma whose size ≤ 5 mm was 42.5％ (311/732);and that of larger size of 6 to 9 mm was 17.8％ (194/1 090);that of even larger size,i.e.,≥10 mm,was 7.6％(34/445)(P＜0.01).Miss rates of Is,Isp,Ip,LST and Ⅱ adenomas in shape were 28.4％(489/1 720),9.3％(24/235),6.6％ (12/182),9.0％(6/67) 20.5％ (8/39) respectively (P＞0.05).Location with highest adenoma miss rate were descending colon,ascending colon and transverse colon,27.8％(64/230),25.5％(120/470),25.5％ (161/632) respectively.Miss rates of high and low risk adenoma were 44.8％ (277/618) and 17.4％ (63/363) (P＜0.01).The highest adenoma miss rate of all the pathology type was tubular adenoma.The adenoma miss rate was 26.9％ (449/1 671) (P＜0.01).Miss rates of good and poor bowel preparation were 30.2％ (271/897) and 82.1％ (69/84) (P＜0.01).Miss rates of adequate and inadequate withdrawal time were 24.3％ (174/717) and 62.9％ (166/264) (P＜0.01).Conclusion Male,old-age,diameter ≤ 5 mm,poor bowel preparation and inadequate withdrawal time,high risk adenoma are the risk factors for missed adenoma.But the shape and location of adenoma are not the risk factors.

Objective: To compare the efficacy of endoscopic treatment with surgical treatment for early gastric cancer accorded with expanded indications of endoscopic submucosal dissection (ESD). Methods: A total of 165 patients (167 lesions) with early gastric cancer underwent ESD (ESD group, 77 cases) or surgery (surgery group, 88 cases) from January 2011 to December 2016. The lesions fulfilled expanded indications of ESD, and were pathologically identified as differentiated or undifferentiated adenocarcinoma. Chi-square test, continuity-adjusted Chi square test, and Fisher exact test were used to analyze the incidence of lesion residual, local recurrence, metachronous recurrence, short-term complications and long-term complications. The 3-year overall survival rate and 3-year disease-free survival rate of the two groups were analyzed by Kaplan-Meier method. Results: There were no differences on the incidence of lesion residual (P=0.473), local recurrence (P=1.000) and metachronous recurrence (P=1.000) between the ESD group and the surgery group. The 3-year overall survival rate (100.0% VS 98.3%, P=0.343) and the 3-year disease-free survival rate (98.1% VS 96.7%, P=0.655) were not significantly different between the two groups. There was no significant difference on the incidence of short-term complications between the two groups [7.8% (6/77) VS 5.7% (5/88), χ²=0.294, P=0.588]. The incidence of long-term complications in the ESD group was lower than that in the surgery group [0 (0/77) VS 8.0% (7/88), continuity-adjusted χ²=4.588, P=0.032]. Conclusion For patients with early gastric cancer fulfilled expanded indications of ESD, ESD has a lower incidence of long-term complications with similar efficacy compared to surgery.

Objective To evaluate the value of near focus narrow-band imaging ( NF-NBI ) in differentiating hyperplastic polyp ( HP ) and sessile serrated adenomas/polyp ( SSA/P ) . Methods Data of 65 cases of pathologically confirmed HP or SSA/P with clear NF-NBI images in Huadong Hospital Affiliated to Fudan University from October 2017 to September 2018 were retrospectively analyzed. Three senior doctors observed the images of NF-NBI, including expanded crypt opening ( ECO ) and thick & branched vessel ( TBV) . The results were compared with pathological results in order to analyze differential diagnostic value of ECO and TBV for HP and SSA/P. Results Among 65 lesions, 44 were SSA/P and 21 were HP. The sensitivity, specificity, and accuracy of ECO, TBV, and ECO combined with TBV for differential diagnosis between HP and SSA/P were 80. 3％( 106/132 ) , 85. 7％( 54/63 ) and 82. 1％( 160/195 ); 38. 6％( 51/132) , 82. 5％( 52/63 ) , and 52. 8％( 103/195 ); and 84. 8％( 112/132 ) , 73. 0％( 46/63 ) , and 81. 0％(158/195), respectively. Conclusion ECO under NF-NBI has a high sensitivity for diagnosis of SSA/P . ECO combined with TBV is helpful for differential diagnosis between HP and SSA/P .

Objective To investigate the risk factors of pathological discrepancy between biopsy and excisional specimen from gastric low-grade intraepithelial neoplasia (LGIN) and early gastric cancer (EGC). Methods A retrospective analysis was conducted on the data of 235 patients who underwent endoscopic submucosal dissection or surgical resection and diagnosed as LGIN or EGC ( including high-grade intraepithelial neoplasia) by postoperative pathology. Patients were grouped by whether there was significant pathological discrepancy between biopsy and excisional specimen. Univariate and multivariate analyses were used to analyze the risk factors for significant pathological discrepancy. Results Significant pathological discrepancy occurred in 33 cases (14. 0%). Univariate analysis showed that protruding lesion, non-reddish surface, without erosion or ulcer, diffused pathological type and number of biopsy were related to the pathological discrepancy (all P＜0. 05). Multivariate analysis suggested that small number of biopsy blocks (OR＝0. 574, 95%CI: 0. 363-0. 908, P＝0. 018) was an independent risk factor for significant pathological discrepancy. Conclusion The pathological discrepancy between biopsy and excisional specimen from gastric LGIN and EGC are common. Multiple biopsies can improve the accuracy of biopsy and reduce the occurrence of pathological discrepancy with excisional specimen.

Objective:To analyze the predictive value of P504S for pathological upgrading of gastric low-grade intraepithelial neoplasia (LGIN) after endoscopic submucosal dissection (ESD).Methods:Data of 117 patients (119 lesions) who underwent ESD for LGIN at Huadong Hospital from January 2015 to March 2019 were analyzed retrospectively. Biopsy and ESD specimens were collected. According to pathology, specimens were divided into the LGIN group (postoperative pathology of non-upgrade) and the upgrade group (postoperative pathology of upgrade). The positive rates of P504S were compared between biopsy and postoperative specimens of the LGIN group, and between biopsy and postoperative specimens of the upgrade group. The consistency of the expression of P504S was examined between the biopsy specimens and the postoperative specimens in the LGIN group and the upgrade group. Receiver operator characteristic (ROC) curve of the prediction of pathological upgrading was drawn by the results of P504S in biopsy, and the cutoff value of immunohistochemical staining score was calculated.Results:The positive rate of P504S in the biopsy specimens of the LGIN group (46.8%, 36/77) was lower than that in the biopsy specimens of the upgrade group (73.2%, 30/41) with significant difference ( P=0.006). The positive rate of P504S in the postoperative specimens of the LGIN group (51.9%, 40/77) was lower than that in the postoperative specimens of the upgrade group (82.9%, 34/41) with significant difference ( P=0.001). In the LGIN group, the positive rate of P504S in biopsy specimens (46.8%, 36/77) was lower than that in postoperative specimens (51.9%, 40/77) without significant difference ( P=0.289). The expression of P504S was consistent between biopsy specimens and postoperative specimens with good consistency( K=0.793, P<0.001). In the upgrade group, the positive rate of P504S in biopsy specimens (73.2%, 30/41) was lower than that in the postoperative specimens (82.9%, 34/41) without significant difference ( P=0.219). The expression of P504S was consistent between biopsy and postoperative specimens, and the consistency was general ( K=0.579, P<0.001). ROC curve was drawn for the prediction of pathological upgrading by the results of P504S in biopsy, and the cutoff value of immunohistochemical staining score was 100. The sensitivity and specificity of pathological upgrading for positive result were 0.659 and 0.740, respectively. Conclusion:P504S staining of the postoperative specimens facilitates identification of the degree of gastric mucosal neoplasia. When the cutoff value of staining score is 100, the staining of P504S in biopsy tissue plays a role in predicting the pathological upgrading.