Clinical efficacy of metformin in familial adenomatous polyposis and the effect of intestinal flora.

BACKGROUND AND AIMS: Metformin has been reported to inhibit the occurrence and development of colorectal cancer (CRC) by mediating changes in intestinal flora. Studies have also indicated that the occurence of familial adenomatous polyposis (FAP) may also be associated with changes in the intestinal flora. Therefore, we investigated the efficacy and safety of metformin in treating FAP and the association with intestinal flora. RESULTS: Compared with the baseline, the mean number and load of polyps in the areas of nanocarbon labeling and postoperative residuals in the test group were lower than those in the placebo group, while the diversity of intestinal flora species was increased. At the genus level, the relative abundance of g_Ruminococcus in the test group was lower than that at baseline, whereas the relative abundance of g_Lactobacillus was higher. These changes were statistically significant (P < 0.05). CONCLUSION: One-year metformin therapy for FAP is safe and effective, potentially mediated by modulating the intestinal flora. This study provides new insights and strategies for preventing adenomatous polyp carcinogenesis in FAP and explores possible preventive action.

Antimicrobial prophylaxis in patients undergoing endoscopic mucosal resection for 10- to 20-mm colorectal polyps: A randomized prospective study.

BACKGROUND AND PURPOSE: Endoscopic mucosal resection (EMR) is frequently used for the removal of colorectal neoplasms. However, the use of prophylactic antibiotics in patients undergoing EMR is debatable. The aim of this randomized controlled trial was to assess whether antimicrobial prophylaxis is crucial in the perioperative period of EMR, especially for 10- to 20-mm lesions in this setting. METHODS: Two hundred and sixty-four patients were randomized equally into 2 groups, the antibiotic (cefixime) group and the control group. The occurrence of adverse events was examined at 1 to 3 days after EMR. Plasma levels of inflammatory markers were analyzed at pre-operation, 1 day post-operation and 3 days post-operation. Blood samples collected at 1 day post-operation were used for culture. RESULTS: A total of 264 and 268 polyps were removed by EMR in the antibiotic group and the control group, respectively. There were 5 cases of fever, with 2 in the antibiotic group and 3 in the control group. In the antibiotic group, 12 patients had abdominal pain and 10 suffered bleeding, whereas in the control group, abdominal pain and bleeding were observed in 10 and 11 patients, respectively. There were no significant differences in the proportion of patients with fever or the incidences of postoperative complications between the groups. No significant differences between the groups were reported in plasma levels of white blood cell count, erythrocyte sedimentation rate, C-reactive protein or procalcitonin at pre-operation or post-operation. No patients provided positive blood cultures. CONCLUSIONS: The use the prophylactic antibiotics for EMR procedures in the perioperative period is no longer required when the lesions are 10 to 20 mm in size.

Usefulness of the combined orthodontic rubber band and clip method for gastric endoscopic submucosal dissection.

BACKGROUND AND AIMS: Effective traction is an important prerequisite for successful endoscopic submucosal dissection (ESD). The combined orthodontic rubber band (ORB) and clip method was effective in colorectal cancer ESD. To date, the method was not reported in gastric ESD. This study aimed to investigate its efficacy and safety for gastric neoplasms ESD. METHODS: We retrospectively analyzed data of 118 patients with gastric neoplasms treated by ESD from November 2020 to April 2022, 43 by ORB-ESD and 75 by the conventional ESD. The primary outcome measure was the ESD procedure time. Clinical data on efficacy and safety were also collected and analyzed. Propensity score matching (PSM) matched the patients in both groups. RESULTS: PSM successfully matched 31 pairs of patients. The ORB-ESD operation time was shorter (median [interquartile range], 35 [30-48] vs. 49 [40-70] min, P < 0.001) and dissection speed was higher (median [interquartile range], 22.6 [14.4-29.3] vs. 13.5 [9.6-17.9] mm2/min, P < 0.001) than in the conventional ESD. The groups were similar in muscular injury rate, frequency and time of use of thermal hemostatic forceps, postoperative adverse events, en bloc resection, and R0 resection rate (P > 0.05). CONCLUSIONS: Compared to the conventional ESD, ORB-ESD significantly reduced the procedure time and increased the dissection speed, proving beneficial to gastric ESD.

Orthodontic Rubber Band-Assisted Endoscopic Submucosal Dissection: An Efficient Method for Treating Superficial Colorectal Tumors.

BACKGROUND: Colorectal endoscopic submucosal dissection (ESD) is a complex operation. Effective traction is crucial. We have successfully used an orthodontic rubber band (ORB) combined with the clip traction method to assist ESD (ORB-ESD). The aim of this retrospective study is to describe the method and to compare the efficacy and safety of ORB-ESD versus conventional ESD in the treatment of superficial colorectal tumors. METHODS: We retrospectively analyzed the data of patients with superficial colorectal tumor (with diameter ≥ 20 mm) who received either ORB-ESD (n = 34) or conventional ESD (n = 90) between January 2019 and September 2020. Propensity score matching (PSM) was used to match the clinical data of 31 pairs of patients in each group. RESULTS: Operation time was significantly shorter for ORB-ESD than for conventional ESD (34.5 minutes vs. 56 minutes, P ≤ 0.001). In the propensity-matched cohorts, the operation time remained significantly shorter in the ORB-ESD patients (35 minutes vs. 50 minutes, P = 0.001). Postoperative adverse events, en bloc resection rate, and R0 resection rate were comparable between the two groups (P > 0.05), both before and after propensity score matching. In the ORB subgroup analysis, the trainee and expert ESD operation times were similar (37 (26-53) vs. 33.5 (26-37) minutes, respectively; P = 0.274). CONCLUSION: ORB-ESD appears to be an effective technique for ESD of colorectal cancer. Our findings need to be confirmed in large prospective multicenter studies.

Oesophageal squamous cell carcinoma mimicking submucosal tumour.

BACKGROUND: Oesophageal submucosal tumours are usually benign. We report a rare case of esophageal squamous cell carcinoma presenting as a submucosal tumour. CASE PRESENTATION: A 58-year-old man undergoing screening oesophago-gastroduodenoscopy was found to have a smooth-surfaced 0.6-cm sized submucosal tumour in the oesophagus 30 cm from the incisor. Endoscopic ultrasonography showed the tumour to be located in the muscularis mucosa; the lesion was heterogeneously hypoechoic and had a clear boundary. With a provisional diagnosis of leiomyoma, the tumour was removed by endoscopic submucosal dissection. Pathological examination showed it to be a moderately differentiated infiltrating squamous cell carcinoma, with normal overlying squamous epithelium. Immunohistochemistry indicated that it was caused by malignant transformation in mucosal glandular duct epithelium. Positron emission tomography-computer tomography showed no tumour spread to any other site. The patient was treated by oesophageal resection. CONCLUSION: The clinician should be aware that oesophageal submucosal tumours with smooth overlying mucosa may not always be benign; malignancy must be ruled out.

Gastric intestinal metaplasia assessment between linked color imaging based on endoscopy and pathology.

OBJECTIVE: Cumulative evidence suggests that linked color imaging (LCI) can be used to identify gastric intestinal metaplasia (GIM). We aimed to develop endoscopic grading for GIM (EGGIM) with LCI. METHODS: Two hundred and seventy-seven patients who underwent high-resolution white-light gastroscopy followed by LCI for EGGIM estimation were included. LCI was performed for the entire mucosa, and images of five areas each were recorded from the lesser and greater curvatures of the antrum and corpus, and for the incisura. For each area, scores of 0 (no GIM), 1 (focal GIM, ≤30% of the area), and 2 (extensive GIM, >30% of the area) were attributed for 10 points. If GIM was suspected based on endoscopy findings, targeted biopsies were performed; if GIM was not evident, random biopsies were performed according to the Sydney system to estimate the operative link on GIM (OLGIM). RESULTS: GIM was staged as OLGIM 0, I, II, III, and IV in 136, 70, 37, 28, and 6 patients, respectively. For OLGIM III/IV diagnosis, the area under the receiver operating curve was 0.949 (95% CI 0.916-0.972). EGGIM of 4, with sensitivity and specificity of 94.12% (95% CI 80.3%-99.3%) and 86.42% (95% CI 81.5%-90.5%), respectively, was determined the best cut-off value for identifying OLGIM III/IV patients. CONCLUSIONS: Our findings demonstrated the ability of EGGIM for diagnosing the extent of intestinal metaplasia and showed that EGGIM is related to OLGIM staging. EGGIM of 4 was the best cut-off value for identifying OLGIM III/IV patients.

Clinical characteristics of non-ampullary duodenal polyps in the elderly and the outcomes of endoscopic mucosal resection.

At present, there are no reports on non-ampullary polyps of the duodenum (NAPDs) in the elderly. The aim of this study was to analyze the clinicopathological features of NAPDs in elderly and non-elderly patients to explore the efficacy and safety of endoscopic mucosal resection (EMR) of NAPDs in the elderly.A total of 110 patients underwent EMR of NAPDs between April 2016 and December 2019. The shape, location, size, postoperative complications, and histopathological types of NAPDs were compared between the elderly group (n = 44) and the non-elderly group (n = 66).Sessile type was the most common form of NAPD in both groups. In the elderly group, the average size of NAPDs was 12.6 ±â€Š3.9 mm. In the non-elderly group, NAPDs had an average size of 10.1 ±â€Š5.8 mm. Complete EMR was performed in both groups. The postoperative complications of EMR did not significantly differ between the 2 groups. Postoperative pathological examination showed that tubular villous adenomas were more common in the elderly group than in the non-elderly group (P = .005), while tubular adenomas were more common in the non-elderly group than in the elderly group (P = .007). Of the 110 patients, 99 completed postoperative follow-up (median follow-up duration, 20.93 months). There were no residual or recurrent lesions.EMR is safe and effective for the treatment of NAPDs in elderly patients.

Endoscopic full-thickness resection of gastric ectopic splenic nodules.

BACKGROUND: Ectopic spleen is extremely rare. Most cases are congenital, acquired ectopic spleen may be a consequence of surgery or trauma to the spleen. The ectopic spleen in the gastric wall we reported is even rarer. CASE PRESENTATION: We report a 41-year-old female patient, with a past history of splenectomy, who presented with heartburn. Gastroscopy revealed a swelling in the fundus in the stomach. Ultrasonography and computed tomographic examination suggested the possibility of gastrointestinal stromal tumor. We performed endoscopic resection of the mass. Pathological examination of the resected mass showed ectopic spleen. CONCLUSION: When a patient with a history of splenectomy presents with a gastric submucosal tumor, ectopic spleen should also be considered in the differential diagnoses. And minimally invasive endoscopic treatment can achieve the purpose of diagnosis and treatment for unobvious submucosal tumors.

An innovative ex-vivo porcine upper gastrointestinal model for submucosal tunnelling endoscopic resection (STER).

Background and study aims: Submucosal tunnelling endoscopic resection (STER) is a novel endoscopic technique to remove submucosal tumour (SMT). We propose a novel, low cost simulator for training of techniques for STER. Patients and methods: The model consisted of an ex-planted porcine oesophagus, stomach and duodenum with marbles embedded surgically in the submucosal plane. Two expert endoscopists with experience in submucosal tunnelling and 5 board-certified endoscopists with no experience in submucosal tunnelling were recruited. Participants were asked to perform a diagnostic endoscopy and 2 STER procedures, 1 in the oesophagus and 1 in the stomach. They also answered a structured questionnaire. Factors including operative time, mucosal and muscular injury rate, injection volume and accuracy of endoscopic closure were assessed. Results: The median time for localization of all SMTs was 40.1 seconds for experts and 38.5 seconds for novices (P = 1.000). For esophageal STER, the length of mucosal incisions and tunnelling distances were comparable between the 2 groups. The median volume injected by the novice group was significantly lower than the experts (15 mL vs 42.5 mL (P = 0.05). The median tunnelling time per length was 25.9 seconds/mm for the experts and 40.8 seconds/mm for the novice group (P = 0.38). There was a higher rate of mucosal injury and muscular perforation in the novice group (8 vs 0; P = 0.05). For gastric STER, the length of mucosal incisions and tunnel distances were comparable between the 2 groups. The median tunnelling time per length for the experts was 23.3 seconds/mm and 34.6 seconds/mm for the novice group (P = 0.38). One mucosal injury was incurred by a novice. The rate of dissection in the stomach and the oesophagus was not statistically different (P = 0.620). All participants voted that the model provides a realistic simulation and recommended it for training. Conclusions: STER is an advanced endoscopic technique where its indication is currently explored. Experienced and novice STER endoscopists have expressed the usefulness of this model as a training tool. This low-cost model can be used for future research in STER.