title: Recurrence after transanal endoscopic microsurgery for large rectal adenomas.
abstract: BACKGROUND
  Transanal endoscopic microsurgery (TEM) has revolutionized the technique and outcome of transanal surgery, becoming the standard of treatment for large sessile rectal adenomas. Nevertheless, only a few studies have evaluated the risk factors for local recurrence in order to recommend a "tailored" approach. The aim of this study was to identify predictor variables for recurrence after TEM to treat rectal adenoma.
  
  
  METHODS
  This study is a retrospective analysis of a prospective database of patients treated for large sessile rectal adenomas by TEM at our institution, with a minimum follow-up of 12 months. Age, gender, tumor diameter, distance from the anal verge, degree of dysplasia, histology, and margin involvement were investigated.
  
  
  RESULTS
  Between January 1993 and July 2010, 293 patients with a rectal adenoma ≥3 cm underwent TEM. Postoperative morbidity rate was 7.2 % (21/293) and there was no 30-day mortality. Over a median follow-up period of 110 (range = 12-216) months, 13 patients (5.6 %) were diagnosed with local recurrence. The median time to recurrence was 10 (range = 4-33) months, with 76.9 % of recurrences detected within 12 months after TEM. At univariate analysis, tumor diameter (p = 0.007), and positive margins (p < 0.001) were shown to be significant risk factors, while multivariate analysis indicated the presence of positive margins as the only independent predictor of recurrence (p = 0.003).
  
  
  CONCLUSIONS
  TEM provides excellent oncological outcomes in the treatment of large sessile benign rectal lesions, assuring a minimal risk of resection margin infiltration at pathology examination, which represents the only risk factor for recurrence.
authors.affiliation: Digestive and Colorectal Surgery and Centre for Minimally Invasive Surgery, Dipartimento di Discipline Medico-Chirurgiche, University of Torino, Corso A. M. Dogliotti 14, 10126 Turin, Italy.
authors.forename: Marco Ettore
authors.initials: ME
authors.lastname: Allaix
authors.forename: Alberto
authors.initials: A
authors.lastname: Arezzo
authors.forename: Paola
authors.initials: P
authors.lastname: Cassoni
authors.forename: Federico
authors.initials: F
authors.lastname: Famiglietti
authors.forename: Mario
authors.initials: M
authors.lastname: Morino
mesh_terms: D000236:Adenoma / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal; D005260:Female; D006801:Humans; D008297:Male; D008866:Microsurgery / Q000379:methods*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D011351:Proctoscopy / Q000379:methods*; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies