title: The "Studded" Rectum: Phenotypic Evidence of MYH-Associated Polyposis.
abstract: BACKGROUND
  MYH-associated polyposis is a recessively inherited syndrome of colorectal cancer predisposition attributed to biallelic germline mutations in the base excision repair gene MYH. Clinically it overlaps with attenuated familial adenomatous polyposis, sporadic oligopolyposis, serrated polyposis, familial colorectal cancer type X, and Lynch syndrome. There is no specific phenotypic feature of MYH-associated polyposis. We have noticed that a proportion of patients with MYH-associated polyposis presenting for yearly colonoscopy surveillance have rectums that are studded with small hyperplastic polyps.
  
  
  OBJECTIVE
  We report this as a possible unique phenotypic feature of the syndrome.
  
  
  METHODS
  This was a descriptive study.
  
  
  METHODS
  The study was conducted at a department of colorectal surgery in a tertiary referral center.
  
  
  METHODS
  Patients affected with oligopolyposis or MYH-associated polyposis presenting for endoscopic surveillance and polyp control were included.
  
  
  METHODS
  Interventions included colonoscopy or proctoscopy with excision or biopsy of mucosal lesions.
  
  
  METHODS
  The presence of rectal studding was measured.
  
  
  RESULTS
  There were 49 patients, 16 with biallelic germline mutations of MYH; 10 of these had rectal studding. A sampling of rectal polyps was biopsied and all were hyperplastic. Five patients with biallelic MYH mutations had no studding, and 1 had not been prospectively examined. The studding was independent of the nature of the MYH mutation(s). The 33 patients other patients included 21 with serrated polyposis, 2 with a germline APC mutation, 1 with a PTEN mutation, 2 with mixed polyposis, 3 with oligoadenomatous polyposis and no germline mutation, and 4 patients with oligoadenomatous polyposis who had not been genetically tested. Only 1 of these (oligoadenomatous polyposis, not tested) had studding.
  
  
  CONCLUSIONS
  The study was limited by its small number of biallelic MYH mutation carriers.
  
  
  CONCLUSIONS
  Rectal studding may be a sign of MYH-associated polyposis and raises questions about the biology of abnormal base excision repair.
authors.affiliation: Department of Colorectal Surgery, Sanford R. Weiss, M.D., Center for Hereditary Colorectal Neoplasia, Digestive Diseases Institute, Cleveland Clinic, Cleveland, Ohio.
authors.forename: James
authors.initials: J
authors.lastname: Church
authors.forename: Sara
authors.initials: S
authors.lastname: Kravochuck
mesh_terms: D011125:Adenomatous Polyposis Coli / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007417:Intestinal Polyps / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011446:Prospective Studies; D012007:Rectum / Q000000981:diagnostic imaging / Q000473:pathology*