Yasushi Yamasaki1, Noriya Uedo2, Takuji Akamatsu3, Tomo Kagawa4, Reiji Higashi5, Osamu Dohi6, Masanori Furukawa7, Yu Takahashi8, Takuya Inoue9, Shouichi Tanaka10, Ryuta Takenaka11, Mikitaka Iguchi12, Takuji Kawamura13, Takao Tsuzuki14, Tomoaki Yamasaki15, Takeshi Yamashina16, Junichiro Nasu17, Tomohiko Mannami18, Atsushi Yamauchi19, Kazuhiro Matsueda20, Shigeyuki Aizawa21, Toshiharu Mitsuhashi22, Hiroyuki Okada1. 1. Department of Gastroenterology, Okayama University Hospital, Okayama, Japan. 2. Department of Gastrointestinal Oncology, Osaka International Cancer Institute, Osaka, Japan. Electronic address: noriya.uedo@oici.jp. 3. Department of Gastroenterology and Hepatology, Japanese Red Cross Society Wakayama Medical Center, Wakayama, Japan. 4. Department of Gastroenterology, Kagawa Prefectural Central Hospital, Takamatsu, Japan. 5. Department of Internal Medicine, Hiroshima City Hiroshima Citizens Hospital, Hiroshima, Japan. 6. Department of Molecular Gastroenterology and Hepatology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan. 7. Division of Endoscopy, Nara Medical University Hospital, Nara, Japan. 8. Third Department of Internal Medicine, Kansai Medical University, Osaka, Japan. 9. Department of Gastroenterology and Hepatology, Osaka General Medical Center, Osaka, Japan. 10. Department of Gastroenterology, National Hospital Organization Iwakuni Clinical Center, Iwakuni, Japan. 11. Department of Internal Medicine, Tsuyama Chuo Hospital, Tsuyama, Japan. 12. Second Department of Internal Medicine, Wakayama Medical University, Wakayama, Japan. 13. Department of Gastroenterology, Kyoto Second Red Cross Hospital, Kyoto, Japan. 14. Department of Internal Medicine, Japanese Red Cross Society Himeji Hospital, Himeji, Japan. 15. Department of Gastroenterology, Osaka City General Hospital, Osaka, Japan. 16. Department of Gastroenterology and Hepatology, Osaka Red Cross Hospital, Osaka, Japan. 17. Department of Internal Medicine, Okayama Saiseikai General Hospital, Okayama, Japan. 18. Department of Gastroenterology, National Hospital Organization Okayama Medical Center, Okayama, Japan. 19. Department of Gastroenterology and Hepatology, Tazuke Kofukai Medical Research Institute, Kitano Hospital, Osaka, Japan. 20. Department of Gastroenterology and Hepatology, Kurashiki Central Hospital, Kurashiki, Japan. 21. Department of Gastroenterology, Nara Prefecture Seiwa Medical Center, Nara, Japan. 22. Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan.
Abstract
BACKGROUND AND AIMS: Endoscopic resection of nonampullary duodenal adenoma is often challenging, and its technique has not yet been standardized. To overcome the practical difficulty of conventional endoscopic mucosal resection, underwater endoscopic mucosal resection (UEMR) was recently developed; therefore, we investigated the effectiveness and safety of UEMR for nonampullary duodenal adenoma. METHODS: A multicenter, prospective cohort study was conducted at 21 institutions in Japan. We enrolled patients with no more than 2 nonampullary duodenal adenomas ≤20 mm in size, who were planned to undergo UEMR. After UEMR, follow-up endoscopies were scheduled at 2 and 12 months after the procedure, and biopsy specimens were taken from the post-UEMR scars. The primary endpoint was the proportion of patients with histologically proven nonrecurrence at follow-up endoscopy and biopsy. RESULTS: A total of 155 patients with 166 lesions underwent UEMR. One patient with a non-neoplastic lesion in the resected specimen and 10 patients with 10 lesions who were lost to follow-up were excluded. Finally, 144 patients with 155 lesions who received all follow-up endoscopies were analyzed for the primary endpoint. The proportion of patients with proven nonrecurrence was 97.2% (n = 140 of 144; 95% confidence interval, 92.8%-99.1%) which exceeded the predefined threshold value (92%). Two cases of delayed bleeding (1.2%) occurred and they were successfully managed by clips. All recurrences were successfully treated by additional endoscopic treatment. CONCLUSIONS: This multicenter, prospective cohort study demonstrated effectiveness and safety of UEMR for nonampullary duodenal adenomas ≤20 mm in size. (University Hospital Medical Network Clinical Trials Registry, Number: UMIN000030414).
BACKGROUND AND AIMS: Endoscopic resection of nonampullary duodenal adenoma is often challenging, and its technique has not yet been standardized. To overcome the practical difficulty of conventional endoscopic mucosal resection, underwater endoscopic mucosal resection (UEMR) was recently developed; therefore, we investigated the effectiveness and safety of UEMR for nonampullary duodenal adenoma. METHODS: A multicenter, prospective cohort study was conducted at 21 institutions in Japan. We enrolled patients with no more than 2 nonampullary duodenal adenomas ≤20 mm in size, who were planned to undergo UEMR. After UEMR, follow-up endoscopies were scheduled at 2 and 12 months after the procedure, and biopsy specimens were taken from the post-UEMR scars. The primary endpoint was the proportion of patients with histologically proven nonrecurrence at follow-up endoscopy and biopsy. RESULTS: A total of 155 patients with 166 lesions underwent UEMR. One patient with a non-neoplastic lesion in the resected specimen and 10 patients with 10 lesions who were lost to follow-up were excluded. Finally, 144 patients with 155 lesions who received all follow-up endoscopies were analyzed for the primary endpoint. The proportion of patients with proven nonrecurrence was 97.2% (n = 140 of 144; 95% confidence interval, 92.8%-99.1%) which exceeded the predefined threshold value (92%). Two cases of delayed bleeding (1.2%) occurred and they were successfully managed by clips. All recurrences were successfully treated by additional endoscopic treatment. CONCLUSIONS: This multicenter, prospective cohort study demonstrated effectiveness and safety of UEMR for nonampullary duodenal adenomas ≤20 mm in size. (University Hospital Medical Network Clinical Trials Registry, Number: UMIN000030414).