title: Transanal endoscopic surgery with total wall excision is required with rectal adenomas due to the high frequency of adenocarcinoma.
abstract: BACKGROUND
  Colorectal adenomatous polyps are considered premalignant lesions, although a high percentage are already malignant at the time of their removal. Full-thickness excision in patients with adenoma detected in preoperative biopsy enables much more accurate pathology examination and has shown that local surgery is appropriate for T1 adenocarcinoma.
  
  
  OBJECTIVE
  To determine whether full-thickness excision during transanal endoscopic surgery is the treatment of choice for rectal adenoma, and to identify possible predictors of invasive adenocarcinoma associated with this type of lesion.
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  The study was conducted at a university teaching hospital.
  
  
  METHODS
  All patients scheduled for transanal endoscopic surgery after detection of adenoma in a preoperative biopsy between June 2004 and February 2013 entered the study.
  
  
  METHODS
  The principal variable was the presence of invasive adenocarcinoma in the pathology study. Other study variables were the epidemiological variables sex and age; the clinical variables tumor size, number of quadrants affected, distance from the anal verge, and tumor location; and the morphological variables tumor aspect, degree of dysplasia, preoperative biopsy (tubulo-villous), endorectal ultrasound, and pelvic MRI stage. Variables found to be related to the risk of malignancy in rectal adenomas were evaluated using univariate and multivariate analysis.
  
  
  RESULTS
  Of 471 patients who underwent surgery, 277 had a preoperative diagnosis of adenoma. Final pathology studies showed 52 (18.8%) invasive adenocarcinomas, among which 27 were pT1 (52%), 16 pT2 (30.7%), and 9 pT3 (17.3%). Factors predictive of invasive adenocarcinoma were sessile morphology (OR 3.2, 95%CI 1.4-7.1), high-grade dysplasia (OR 2.3, 95%CI 1.2-4.8), and endorectal ultrasound stage uT2-T3 (OR 3.8, 95%CI 1.6-9).
  
  
  CONCLUSIONS
  The limitations are derived from the observational design.
  
  
  CONCLUSIONS
  In this sample, half of the adenocarcinomas from adenomas were T1 adenocarcinomas. Because a high proportion of rectal adenomas are, in fact, invasive adenocarcinomas, full-thickness excision is appropriate.
authors.affiliation: 1Coloproctology Unit, General and Digestive Surgery Service, Parc Taulí University Hospital, Universidad Autonoma de Barcelona, Sabadell (Barcelona), Spain 2Pathology Service, Parc Taulí University Hospital, Universidad Autonoma de Barcelona, Sabadell (Barcelona), Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Serra-Aracil
authors.forename: Aleidis
authors.initials: A
authors.lastname: Caro-Tarrago
authors.forename: Laura
authors.initials: L
authors.lastname: Mora-López
authors.forename: Alex
authors.initials: A
authors.lastname: Casalots
authors.forename: Pere
authors.initials: P
authors.lastname: Rebasa
authors.forename: Salvador
authors.initials: S
authors.lastname: Navarro-Soto
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery*; D000236:Adenoma / Q000473:pathology / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011351:Proctoscopy / Q000379:methods*; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012007:Rectum / Q000473:pathology / Q000601:surgery*