title: Risk of developing metachronous colon neoplasm after polypectomy: comparison of one-stage versus two-stage polypectomy.
abstract: BACKGROUND
  The impact of one-stage polypectomy (removal of all neoplasms during diagnostic colonoscopy) versus two-stage polypectomy (removal of all neoplasms during therapeutic colonoscopy following the initial diagnostic colonoscopy) on the development of metachronous neoplasms is poorly understood. Our aim was to compare the effects of one- versus two-stage polypectomy on the development of metachronous neoplasms
  
  
  METHODS
  We retrospectively reviewed the medical records of 249 patients in a tertiary center who underwent one-stage polypectomy, which was followed by one or more surveillance colonoscopy. The development of metachronous neoplasm in this group was compared with that of an age- and sex-matched two-stage polypectomy group consisting of 498 patients
  
  
  RESULTS
  In total, 346 (46.3 %) patients developed any metachronous neoplasm and 29 (3.9 %) patients developed advanced metachronous neoplasm. The 5 years cumulative incidences of any and advanced metachronous neoplasm were 46.2 and 5.0 %, respectively, in the one-stage group, which are not significantly different from the rates of 50.7 and 3.3 % in the two-stage group (p = 0.94 and 0.30, respectively). The only significant risk factor for developing any metachronous neoplasm was ≥ 3 neoplasms at the baseline polypectomy [hazard ratio (HR) 1.75; 95 % confidence interval (CI) 1.41-2.17; p < 0.001]. The only significant risk factor for developing advanced metachronous neoplasm was advanced neoplasm at the baseline polypectomy (HR 2.37; 95 % CI 1.16-4.84; p = 0.01). One- and two-stage polypectomy did not affect the development rates of metachronous neoplasm
  
  
  CONCLUSIONS
  The risks of developing metachronous neoplasm may be similar following one- and two-stage polypectomy.
authors.affiliation: Department of Gastroenterology and Inflammatory Bowel Disease Center, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 138-736, Korea.
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Park
authors.forename: Jong Wook
authors.initials: JW
authors.lastname: Kim
authors.forename: Sang Hyoung
authors.initials: SH
authors.lastname: Park
authors.forename: Dong-Hoon
authors.initials: DH
authors.lastname: Yang
authors.forename: Kee Wook
authors.initials: KW
authors.lastname: Jung
authors.forename: Kyung Jo
authors.initials: KJ
authors.lastname: Kim
authors.forename: Byong Duk
authors.initials: BD
authors.lastname: Ye
authors.forename: Seung-Jae
authors.initials: SJ
authors.lastname: Myung
authors.forename: Suk-Kyun
authors.initials: SK
authors.lastname: Yang
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Kim
authors.forename: Jeong-Sik
authors.initials: JS
authors.lastname: Byeon
mesh_terms: D003110:Colonic Neoplasms / Q000453:epidemiology* / Q000209:etiology; D003111:Colonic Polyps / Q000175:diagnosis / Q000601:surgery*; D003113:Colonoscopy / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000209:etiology; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors