Background/Aims: Although various solutions are being tested for submucosal injection during endoscopic resection, ideal solution has not been established yet. We performed an animal study to evaluate the possibility of sodium alginate as an ideal submucosal injection solution for endoscopic mucosal resection (EMR). Methods: To compare the lesion-lifting properties of different solutions, injection was done to the submucosal layer of porcine stomach. Then the height of mucosal elevation was measured. In addition, EMR was performed after submucosal injection of sodium alginate solution in six dogs. Two were euthanized after 30 minutes of endoscopic observation while the others were euthanized after 1-4 weeks. Retrieved stomachs were examined microscopically. Results: Sodium alginate and sodium hyaluronate solutions maintained longer elevation of the submucosal layer than other solutions. There was no significant difference in the height between two solutions. A clear separation of the mucosal layer from the proper muscle layer was achieved by injecting sodium alginate solution. Histological examination of EMR-induced artificial ulcers revealed no apparent tissue damage and showed normal healing process. Conclusions: Sodium alginate solution creates a sufficient submucosal fluid cushion without apparent tissue damage. It can be considered as an effective submucosal injection material.

Backgroud/Aims: Distinguishing benign and malignant lymph nodes by the findings of endoscopic ultrasonography (EUS) is still controversial. We tried to evaluate EUS findings of benign mediastinal and abdominal lymphadenopathy (BLAP) confirmed by EUS-guided fine needle aspiration (FNA). Methods: A total of 37 patients with enlarged mediastinal or abdominal lymph nodes (diameter ≥1 cm) were enrolled and EUS-FNA was performed. Final diagnosis was based on FNA cytology and follow up imaging studies (CT scans or EUS). Results: Thirteen patients were confirmed to have BLAP by EUS-FNA. Causes of BLAP were as follows; (i) extrapulmonary tuberculosis in six cases including patients with postoperative states due to cervical cancer and advanced gastric cancer, (ii) Kikuchi disease in one case, (iii) hypereosinophilic syndrome in one case, (iv) reactive hyperplasia in five cases including patients with postoperative states due to thyroid cancer, lung cancer, and EGC with ESD. EUS findings of BLAP revealed that median lymph node size was 24.7 mm. Lymph nodes were oval or round shaped in 9 cases, sharp borders in 9 cases, hypoechoic echo pattern in 7 cases, heterogenous internal echo pattern in 7 cases. Other findings included internal septation, calcification, multiplicity, attachment to the gastrointestinal tract wall, and conglomeration. Conclusions: EUS findings of BLAP were not different from those of malignant lymphadenopathy previously reported in other studies.

Background/Aims: There have been few multicenter studies on colonic polyps conducted by primary medical institutions. This study examined the detection rate of colonic polyps in primary health care institutions and the related factors while following the guidelines. Methods: The medical records of 14,029 patients who underwent colonoscopy between January-June 2020 at 40 primary medical institutions in Korea were analyzed. High-risk adenoma was defined as advanced adenoma, carcinoma, or ≥3 adenomas. Results: Most patients (71.2%) aged ≥50 years underwent re-colonoscopy within 5 years (51.3%) for diagnostic purposes (61.3%) in Korean primary medical institutions. The detection rates of colon polyps, adenoma, advanced adenoma, high-risk adenoma, and carcinoma was 59.9%, 38.9%, 5.9%, 11.4%, and 0.3% in all subjects and 59.8%, 37.5%, 8.5%, 12.9%, and 0.3% in average-risk patients, respectively. The incidences of adenoma in average-risk patients increased significantly with age (30s/40s/50s: 20.1%/29.4%/43% for adenoma, 4.4%/6.7%/10.3% for advanced adenoma, and 5.6%/9.5%/14.6% for high-risk adenoma; p<0.05). Before 50 years of age, high-risk adenoma was detected in 9.1% of patients in the first-time screening group, and the significant risk factors were being male and ≥40 years of age. The detection rate of high-risk adenoma in the normal index colonoscopy group within 5 years was 9.0%. The significant risk factors included older age, male sex, positive fecal occult blood test, stool form changes, and nonspecific symptoms (gas and indigestion). Conclusions: More colonic adenoma studies targeting real-world clinical practice will be needed to revise the Korean guidelines for colorectal cancer screening and surveillance.

No abstract

No abstract