title: Is endoscopic ultrasonography essential for endoscopic resection of small rectal neuroendocrine tumors?
abstract: OBJECTIVE
  To evaluate the importance of endoscopic ultrasonography (EUS) for small (≤ 10 mm) rectal neuroendocrine tumor (NET) treatment.
  
  
  METHODS
  Patients in whom rectal NETs were diagnosed by endoscopic resection (ER) at the Pusan National University Yangsan Hospital between 2008 and 2014 were included in this study. A total of 120 small rectal NETs in 118 patients were included in this study. Histologic features and clinical outcomes were analyzed, and the findings of endoscopy, EUS and histology were compared.
  
  
  RESULTS
  The size measured by endoscopy was not significantly different from that measured by EUS and histology (r= 0.914 andr= 0.727 respectively). Accuracy for the depth of invasion was 92.5% with EUS. No patients showed invasion of the muscularis propria or metastasis to the regional lymph nodes. All rectal NETs were classified as grade 1 and demonstrated an L-cell phenotype. Mean follow-up duration was 407.54 ± 374.16 d. No patients had local or distant metastasis during the follow-up periods.
  
  
  CONCLUSIONS
  EUS is not essential for ER in the patient with small rectal NETs because of the prominent morphology and benign behavior.
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Su Bum
authors.initials: SB
authors.lastname: Park
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Dong Jun
authors.initials: DJ
authors.lastname: Kim
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Hyung Wook
authors.initials: HW
authors.lastname: Kim
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Cheol Woong
authors.initials: CW
authors.lastname: Choi
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Dae Hwan
authors.initials: DH
authors.lastname: Kang
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Su Bum Park, Dong Jun Kim, Hyung Wook Kim, Cheol Woong Choi, Dae Hwan Kang, Su Jin Kim, Hyeong Seok Nam, Department of Internal Medicine, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnam-do 626-770, South Korea.
authors.forename: Hyeong Seok
authors.initials: HS
authors.lastname: Nam
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019160:Endosonography; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D018358:Neuroendocrine Tumors / Q000473:pathology / Q000601:surgery*; D011351:Proctoscopy / Q000379:methods*; D012004:Rectal Neoplasms / Q000473:pathology / Q000601:surgery*; D012007:Rectum / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D055815:Young Adult
keywords: Endoscopic ultrasonography; Endoscopy; Histology; Neuroendocrine tumor; Rectal; Small