title: Endoscopic submucosal tunnel dissection of upper gastrointestinal submucosal tumors: A comparative study of hook knifevshybrid knife.
abstract: OBJECTIVE
  To compare the efficacy and safety of a hook knife (HO) with a hybrid knife (HK) during endoscopic submucosal tunnel dissection (ESTD) procedure.
  
  
  METHODS
  Between August 2012 and December 2015, the ESTD procedure was performed for 83 upper GI submucosal lesions, which originated from the muscularis propria layer identified by upper endoscopy and endoscopic ultrasonography. Of these, 34 lesions were treated by a HO, whereas 49 lesions were treated by a HK. Data regarding age, gender, presenting symptoms, tumor location and size, procedure time, complications,en blocresection rate and others were analyzed and compared between the two groups.
  
  
  RESULTS
  There were no significant differences in the age, gender, presenting symptoms and tumor location between the two groups. ESTD was successfully completed in all the patients, and no case was converted to laparoscopy. The mean procedure time was significantly shorter in the HK group than in the HO group (41.3 ± 20.3 minvs57.2 ± 28.0 min,P= 0.004). The mean frequency of device exchange was 1.4 ± 0.6 in the HK group and significantly less than 3.3 ± 0.6 in the HO group (P< 0.001). The differences in tumor size and histopathological diagnoses were not significant between the two groups (P= 0.813,P= 0.363, respectively). Both groups had an equalen blocresection rate and complete resection rate. Additionally, the complication rate was similar between the two groups (P= 0.901). During the follow-up, no recurrence occurred in either group.
  
  
  CONCLUSIONS
  We demonstrate for the first time that HO and HK do not differ in efficacy or safety, but HK reduces the frequency of device exchange and procedure time.
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Jie-Qiong
authors.initials: JQ
authors.lastname: Zhou
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Tang
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Yu-Tang
authors.initials: YT
authors.lastname: Ren
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Zheng-Jie
authors.initials: ZJ
authors.lastname: Wei
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Si-Lin
authors.initials: SL
authors.lastname: Huang
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Qiao-Ping
authors.initials: QP
authors.lastname: Gao
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Zhang
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Yang
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Gong
authors.affiliation: Jie-Qiong Zhou, Si-Lin Huang, Qiao-Ping Gao, Wei Gong, Bo Jiang, Guangdong Provincial Key Laboratory of Gastroenterology, Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D000069916:Endoscopic Mucosal Resection / Q000009:adverse effects / Q000295:instrumentation*; D016145:Endoscopy, Digestive System / Q000379:methods*; D019160:Endosonography; D005260:Female; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D061646:Operative Time; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: Clinical outcome; Endoscopic submucosal tunnel dissection; Hook knife; Hybrid knife; Submucosal tumor