title: An alternative option for "resect and discard" strategy, using magnifying narrow-band imaging: a prospective "proof-of-principle" study.
abstract: BACKGROUND
  The "resect and discard" strategy is beneficial for cost savings on screening and surveillance colonoscopy, but it has the risk to discard lesions with advanced histology or small invasive cancer (small advanced lesion; SALs). The aim of this study was to prove the principle of new "resect and discard" strategy with consideration for SALs using magnifying narrow-band imaging (M-NBI).
  
  
  METHODS
  Patients undergoing colonoscopy at a tertiary center were involved in this prospective trial. For each detected polyp <10 mm, optical diagnosis (OD) and virtual management ("leave in situ", "discard" or "send for pathology") were independently made using non-magnifying NBI (N-NBI) and M-NBI, and next surveillance interval were predicted. Histological and optical diagnosis results of all polyps were compared.
  
  
  RESULTS
  While the management could be decided in 82% of polyps smaller than 10 mm, 24/31 (77%) SALs including two small invasive cancers were not discarded based on OD using M-NBI. The sensitivity [90% confidence interval (CI)] of M-NBI for SALs was 0.77 (0.61-0.89). The risk for discarding SALs using N-NBI was significantly higher than that using M-NBI (53 vs. 23%, p = 0.02). The diagnostic accuracy (95% CI) of M-NBI in distinguishing neoplastic from non-neoplastic lesions [0.88 (0.86-0.90)] was significantly better than that of N-NBI [0.84 (0.82-0.87)] (p = 0.005).
  
  
  CONCLUSIONS
  The results of our study indicated that our "resect and discard" strategy using M-NBI could work to reduce the risk for discarding SALs including small invasive cancer (UMIN-CTR, UMIN000003740).
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. takeuti-yo@mc.pref.osaka.jp.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Takeuchi
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. m-hanafusa@nyc.odn.ne.jp.
authors.forename: Masao
authors.initials: M
authors.lastname: Hanafusa
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. kanzaki@qc4.so-net.ne.jp.
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Kanzaki
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. tks.ohta@gmail.com.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohta
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. hanaoka-no@mc.pref.osaka.jp.
authors.forename: Noboru
authors.initials: N
authors.lastname: Hanaoka
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. yamamoto-sa@mc.pref.osaka.jp.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. higasino-ko@mc.pref.osaka.jp.
authors.forename: Koji
authors.initials: K
authors.lastname: Higashino
authors.affiliation: Department of Pathology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, 537-8511, Japan. yasuhiko-tomita@umin.ac.jp.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tomita
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. uedou-no@mc.pref.osaka.jp.
authors.forename: Noriya
authors.initials: N
authors.lastname: Uedo
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. isihara-ry@mc.pref.osaka.jp.
authors.forename: Ryu
authors.initials: R
authors.lastname: Ishihara
authors.affiliation: Department of Gastrointestinal Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka, 537-8511, Japan. iisi-hi@mc.pref.osaka.jp.
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iishi
mesh_terms: D000368:Aged; D003111:Colonic Polyps / Q000175:diagnosis*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008297:Male; D008875:Middle Aged; D062048:Narrow Band Imaging / Q000379:methods*; D011446:Prospective Studies; D015203:Reproducibility of Results
keywords: Colon polyp surveillance; Colonoscopy; Colorectal neoplasm; Magnifying narrow-band imaging; Resect and discard