title: Lymph node size is not a reliable criterion for predicting nodal metastasis in rectal neuroendocrine tumours.
abstract: OBJECTIVE
  The study was designed to assess the correlation between lymph node (LN) size and LN metastasis in patients with rectal neuroendocrine tumours (NETs).
  
  
  METHODS
  Forty patients who underwent curative resection with lymphadenectomy for a rectal NET between January 2007 and December 2012 were included. The short and long diameters of entire nodes were microscopically measured using a slide gauge.
  
  
  RESULTS
  In all, 1052 LNs were collected from the 40 patients, with 49 (4.7%) showing evidence of metastasis. Metastasis-positive LNs had significantly greater long and short diameters (P < 0.001) than metastasis-negative LNs. Of the 49 metastatic LNs, 29 (59.2%) were ≤ 5 mm in largest diameter. In five patients, the largest metastatic LN was only 2-3 mm in diameter. In clinically node-negative (cN0) patients, 18 (51.4%) patients had metastatic LNs (pN1).
  
  
  CONCLUSIONS
  The size of LNs containing metastasis varied widely, with some being very small. LN size alone is therefore not a sufficient predictor of tumour metastasis in rectal NETs. Radical surgery with lymphadenectomy should be considered for patients with rectal NETs with high risk factors for LN metastasis, even those without LN enlargement.
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.
authors.forename: B C
authors.initials: BC
authors.lastname: Kim
authors.affiliation: Department of Pathology, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.
authors.forename: Y E
authors.initials: YE
authors.lastname: Kim
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.|Department of Pathology, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.
authors.forename: H J
authors.initials: HJ
authors.lastname: Chang
authors.affiliation: Department of Pathology, Daehang Hospital, Seoul, Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Surgery, Daehang Hospital, Seoul, Korea.
authors.forename: E G
authors.initials: EG
authors.lastname: Youk
authors.affiliation: Department of Surgery, Daehang Hospital, Seoul, Korea.
authors.forename: D-S
authors.initials: DS
authors.lastname: Lee
authors.affiliation: Department of Surgery, Daehang Hospital, Seoul, Korea.
authors.forename: J B
authors.initials: JB
authors.lastname: Lee
authors.affiliation: Department of Surgery, Daehang Hospital, Seoul, Korea.
authors.forename: E-J
authors.initials: EJ
authors.lastname: Lee
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.
authors.forename: D K
authors.initials: DK
authors.lastname: Sohn
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi, Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Oh
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000473:pathology* / Q000601:surgery; D012004:Rectal Neoplasms / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D012307:Risk Factors
keywords: Rectum; carcinoid; lymph node; metastasis; neuroendocrine tumour