Novel beagle model of gastric local fibrotic target lesions for the evaluation and training of endoscopic techniques.

BACKGROUND: Novel endoscopic techniques used in the treatment of gastric lesions with local submucosal fibrosis need preclinical evaluation and training due to safety limitations. Therefore, the purpose of our study was to establish an animal model of gastric local fibrotic target lesions and assess its feasibility in the evaluation and training of endoscopic techniques. METHODS: In six experimental beagles, a 50% glucose solution was injected into three submucosal areas of the fundus, body, and antrum of the stomach to create gastric local fibrotic target lesions (experimental group). On post-injection day (PID) 7, the injection sites were assessed endoscopically to confirm the presence of submucosal fibrosis formation, and the dental floss clip traction assisted endoscopic submucosal dissection (DFC-ESD) procedure was performed on the gastric local fibrotic target lesions to confirm its feasibility after endoscopic observation. The normal gastric mucosa of six control beagles underwent the same procedure (control group). All the resected specimens were evaluated by histological examination. RESULTS: All 12 beagles survived without postoperative adverse events. On PID 7, 16 ulcer changes were observed at the injection sites (16/18) under the endoscope, and endoscopic ultrasonography confirmed the local submucosal fibrosis formation in all ulcer lesions. The subsequent DFC-ESD was successfully performed on the 32 gastric target lesions, and the mean submucosal dissection time in the ulcer lesions was greater than that in the normal gastric mucosa (15.3 ± 5.6 vs. 6.8 ± 0.8 min; P < 0.001). There was no difference in rates of en bloc resection, severe hemorrhage, or perforation between the two groups. Histological analysis of the ulcer lesions showed the absence of epithelial or muscularis mucosae and extensive submucosal fibrous tissue proliferations compared with normal gastric mucosa. Overall, endoscopists had high satisfaction with the realism and feasibility of the animal model. CONCLUSION: We developed a novel animal model of gastric local fibrotic target lesions to simulate difficult clinical situations, which strongly appeared to be suitable for the preclinical evaluation and learning of advanced endoscopic techniques.

Metformin combined with endoscopic therapy in patients with familial polyposis associated with carcinoma: A case report.

RATIONALE: Familial adenomatous polyposis (FAP) is an autosomal dominant genetic disease, with a very high cancer rate. At present, endoscopic resection of polyps ≥ 1 cm is often chosen for patients with non-cancerous polyps who are unwilling to undergo surgery, and regular review is conducted. Once the polyps are pathologically confirmed to be cancerous, surgical resection of the diseased large intestine is generally recommended, but surgery often leads to a series of complications. So what do you do with cancer patients who don't want surgery? PATIENT CONCERNS: A 19-year-old woman presented with intermittent hematochezia with abdominal pain. A colonoscopy revealed hundreds of intestinal polyps. DIAGNOSES: The patient had a family history of FAP, and there were hundreds of polyps in the intestine. The pathology was adenomatous, and some polyps became cancerous, which met the diagnostic criteria of FAP. INTERVENTIONS: Endoscopic examination was arranged for the patient, the resection of intestinal polyps ≥ 1 cm was given priority, and other polyps were removed as far as possible. After that, metformin 500 mg orally was given twice a day, and endoscopic follow-up was conducted every 6 months. During each endoscopic follow-up, intestinal polyps ≥ 1 cm were preferred to be removed, and other polyps were removed as far as possible. OUTCOMES: The patient's abdominal pain and blood in the stool disappeared after endoscopic treatment. Cancerous polyps were found at the second and third follow-up visits, but the patient always refused surgical treatment. After 4 years of follow-up, polyp load was significantly reduced, abdominal pain and bloody stool symptoms did not appear again, and imaging examination showed no tumor recurrence and metastasis. LESSONS: Endoscopic polyp resection is an important method to treat the clinical symptoms of FAP. Metformin combined with endoscopic therapy is a good alternative for patients with familial polyposis who do not want surgery. When the polyp is cancerous and the polyp is radically resected by the endoscope, if the patient refuses additional surgery, oral metformin combined with endoscopic follow-up can be considered.