Open Access Research article

Improvement of endocytoscopic findings after per oral endoscopic myotomy (POEM) in esophageal achalasia; does POEM reduce the risk of developing esophageal carcinoma? Per oral endoscopic myotomy, endocytoscopy and carcinogenesis

Hitomi Minami1, Naoyuki Yamaguchi1, Kayoko Matsushima1, Yuko Akazawa1, Ken Ohnita1, Fuminao Takeshima1, Toshiyuki Nakayama2, Tomayoshi Hayashi2, Haruhiro Inoue3, Kazuhiko Nakao1 and Hajime Isomoto1*

Author Affiliations

1 Department of Gastroenterology and Hepatology, Nagasaki University Hospital, 1-7-1, Sakamoto, Nagasaki 852-8501, Japan

2 Department of Pathology, Nagasaki University Hospital, 1-7-1, Sakamoto, Nagasaki, 852-8501, Japan

3 Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama, Japan

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BMC Gastroenterology 2013, 13:22  doi:10.1186/1471-230X-13-22

Published: 30 January 2013



Per oral endoscopic myotomy (POEM) has been reported to be a new therapeutic option for esophageal achalasia. The possibility that POEM could reduce the risk of developing esophageal squamous cell carcinoma was evaluated.


This was a single-centre, retrospective study. Fifteen consecutive patients with esophageal achalasia who underwent POEM in our institution between August 2010 and January 2012 were enrolled. Ultra-high magnification with endocytoscopy was performed, and both histopathological and immunohistochemical evaluations for Ki-67 and p53 were assessed before and 3 months after POEM.


POEM was successfully performed and effectively released the dysphagia symptom in all patients without severe complications. Subjective symptoms (mean Ekcardt score, before 7.4 vs. after 0.5, p<0.05) and manometric pressure studies (mean lower esophageal sphincter pressure), before 82.7 vs. after 22.9 mmHg, p<0.05) showed substantial improvement following POEM. The average numbers of esophageal epithelial nuclei before and after POEM on endocytoscopic images were 128.0 and 78.0, respectively (p<0.05). The mean Ki-67-positive ratio was 26.0 (median 25.4, range, 10.3-33.2) before and 20.7 (median 20.0, 13.1-29.9; p=0.07) after POEM, and the mean p53-positive ratio was 2.35 (median 2.61, 0.32-4.23) before and 0.97 (median 1.49, 0.32-1.56; p<0.05) after POEM. A significant positive correlation was seen between the number of nuclei and the Ki-67-positive ratio (p<0.05).


POEM appears to be an effective and less invasive treatment of choice against achalasia and may reduce the risk of esophageal carcinogenesis. Endocytoscopy can be useful for the assessment of esophageal cellular proliferation.

Esophageal achalasia; POEM; Per-oral endoscopic myotomy; Esophageal cancer; Squamous cell carcinoma