title: Sites of surgical wasting in the abdominoperineal specimen.
abstract: BACKGROUND
  In the abdominoperineal excision (APE) specimen 'surgical wasting' has been described, where the least amount of tissue covers the rectum. This is associated with high positive margin rates. The aim of this study was to locate the site of surgical wasting, namely the least amount of tissue excised at APE.
  
  
  METHODS
  Distances from the anal verge to the distal and proximal edges of the sphincter, puborectalis and levator muscles were measured in 12 patients using morphological features on magnetic resonance images. Distances from the mucularis propria to the outer surface of the pelvic muscles and the outer edge of the specimen were measured on axial images. The height from the anal verge at which axial measurements of tissue were minimal was determined.
  
  
  RESULTS
  The presence of a surgical waist between 35 and 42 mm above the anal verge, corresponding to the puborectalis, was confirmed. A smaller amount of perirectal tissue was resected at this level than at other heights (P < 0.001).
  
  
  CONCLUSIONS
  Because less tissue is excised at the puborectalis, careful dissection along the levator plane is necessary, especially if tumour is present. More radical excision of the levators and puborectalis may be of benefit in such patients.
authors.affiliation: Pelican Cancer Foundation, North Hampshire Hospital, Basingstoke, London, UK.
authors.forename: G
authors.initials: G
authors.lastname: Salerno
authors.forename: I
authors.initials: I
authors.lastname: Chandler
authors.forename: A
authors.initials: A
authors.lastname: Wotherspoon
authors.forename: K
authors.initials: K
authors.lastname: Thomas
authors.forename: B
authors.initials: B
authors.lastname: Moran
authors.forename: G
authors.initials: G
authors.lastname: Brown
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001003:Anal Canal / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery; D000704:Analysis of Variance; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery; D012007:Rectum / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery; D016896:Treatment Outcome