title: Rectum-sparing surgery may be appropriate for biallelic MutYH-associated polyposis.
abstract: OBJECTIVE
  The risk of cancer or severe polyposis of the rectal stump after total colectomy for MutYH-associated polyposis is scarcely defined. To evaluate this risk, we describe the findings of endoscopic surveillance of the rectal stump in a series of patients with biallelic MutYH mutations and polyposis.
  
  
  METHODS
  This is a retrospective, observational, multicenter case series derived from 2 familial cancer registries. Biallelic, germ-line MutYH mutations were found in 14 patients with no adenomatous polyposis coli gene mutations. Eleven of them underwent total colectomy with ileorectal anastomosis and yearly proctoscopic surveillance thereafter. Phenotype and histology of rectal polyps were recorded at diagnosis and during follow-up. Development of adenomas and carcinomas during endoscopic surveillance of the rectal stump was observed.
  
  
  RESULTS
  At diagnosis, 6 patients had attenuated polyposis (10-100 adenomas), 5 patients had classical polyposis, 8 patients had colon carcinoma, and no patient had rectal carcinoma. The mean number of rectal polyps at diagnosis was 2.64 ± 2.11 (range, 0-6). No patients had rectal cancer. The most frequent MutYH mutations were Y165C/Y165C and G382D/G382D in 6 and 2 patients, respectively. During surveillance of the rectal stump after surgery (median duration, 5 y; range, 2-23 y), no patient developed rectal cancer. The mean number of adenomas per proctoscopy was 1.23 ± 2.19 (range, 0-10 adenomas per proctoscopy). This study was limited by the small size and retrospective nature of the case series.
  
  
  CONCLUSIONS
  Total colectomy with ileorectal anastomosis may be appropriate for patients with MutYH-associated polyposis, provided that they have no rectal cancer or severe rectal polyposis at presentation and that they undergo yearly endoscopic surveillance thereafter.
authors.affiliation: Department of Medical and Surgical Sciences, University of Brescia, Brescia, Italy. nascimbr@med.unibs.it
authors.forename: Riccardo
authors.initials: R
authors.lastname: Nascimbeni
authors.forename: Salvatore
authors.initials: S
authors.lastname: Pucciarelli
authors.forename: Diego
authors.initials: D
authors.lastname: Di Lorenzo
authors.forename: Emanuele
authors.initials: E
authors.lastname: Urso
authors.forename: Claudio
authors.initials: C
authors.lastname: Casella
authors.forename: Marco
authors.initials: M
authors.lastname: Agostini
authors.forename: Donato
authors.initials: D
authors.lastname: Nitti
authors.forename: Bruno
authors.initials: B
authors.lastname: Salerni
mesh_terms: D000236:Adenoma / Q000235:genetics; D000328:Adult; D000368:Aged; D000483:Alleles; D000714:Anastomosis, Surgical; D002851:Chromatography, High Pressure Liquid; D003082:Colectomy; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000601:surgery*; D045647:DNA Glycosylases / Q000235:genetics*; D005260:Female; D006801:Humans; D044483:Intestinal Polyposis / Q000235:genetics* / Q000601:surgery*; D007558:Italy; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D010375:Pedigree; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011159:Population Surveillance; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric
chemical_list: D045647:DNA Glycosylases; C061738:mutY adenine glycosylase