title: [Transanal endoscopic microsurgery for rectal intraepithelial neoplasia and early rectal carcinoma].
abstract: OBJECTIVE
  To investigate the clinical value of transanal endoscopic microsurgery (TEM) for rectal intraepithelial neoplasia (IN) and early rectal carcinoma.
  
  
  METHODS
  Fifteen patients with rectal tumor were selected to undergo local excision by TEM. The pre-operative diagnosis by biopsy and endoanal ultrasonography (EUS): rectal low-grade IN in 8 cases, high-grade IN in 4 and early rectal carcinoma in 3. The average distance of tumors from the anal verge was 7.2(4-15) cm. The average tumor size was 1.8(1-4) cm. The average proportion of the circumference of bowel lumen involved was 20%(10%-40%).
  
  
  RESULTS
  All the 15 rectal tumors were achieved complete excision (submucosal excision in 5, full-thickness excision in 10), and all the resection margins were clear. The average operating time was 57 (40-90) min. The average blood loss was 35 (10-60) ml. The average post-operative stay was 4.5 (2-9) d. The post-operative pathological diagnosis: rectal low-grade IN in 5 cases, high-grade IN in 6, early submucous invasive carcinoma (pT(1)) in 2, advanced carcinoma (pT(2)) in 2. The diagnostic accuracy of EUS in assessing invasive depth of rectal tumor was 86.7% (13/15). The average follow-up period of 15 patients was 6 (2-10) months. There was no local recurrence occurred.
  
  
  CONCLUSIONS
  TEM is an ideal minimally invasive procedure for the treatment of rectal IN and early rectal carcinoma, with excellent exposure and accurate excision, providing a high-quality tumor specimen for pathological staging. Pre-operative EUS is very important in selecting patients suitable for resection by TEM.
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100730, China.
authors.forename: Guo-le
authors.initials: GL
authors.lastname: Lin
authors.forename: Hui-zhong
authors.initials: HZ
authors.lastname: Qiu
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.forename: W C S
authors.initials: WC
authors.lastname: Meng
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000601:surgery*; D004724:Endoscopy; D005260:Female; D006801:Humans; D008297:Male; D008866:Microsurgery; D008875:Middle Aged; D012004:Rectal Neoplasms / Q000601:surgery*; D012007:Rectum / Q000473:pathology / Q000601:surgery*