title: Lymph node evaluation and survival in colorectal cancer: review of population-based, prospective studies.
abstract: OBJECTIVE
  The total number of lymph nodes retrieved, the number of positive nodes, and/or their ratio are used to evaluate the degree of progression of colorectal cancer. The aim of the present study is to review the relevant literature in order to improve lymph node evaluation and the quality of clinical practice.
  
  
  METHODS
  The English language literature on large, population-based, prospective clinical studies of the evaluation of lymph nodes in colorectal cancer was reviewed. This review focuses on the lymph node harvest (LNH) and the lymph node ratio (LNR), and the survival was also assessed.
  
  
  RESULTS
  The LNH was influenced by patient age, tumor size, Dukes' stage, preoperative radiotherapy, operative urgency, specimen length, pathology template, and academic status of the hospital. Many prospective studies demonstrated a significant correlation between high LNH and increased survival. LNR is an independent prognostic indicator for stage III colorectal cancer. However, there were many different cut-off values allowing for the optimal separation of subgroups according to survival.
  
  
  CONCLUSIONS
  To improve lymph node evaluation and the quality of clinical practice, daily collaboration between surgeons and pathologists is important. Scientific evidence for reasonable and practical LNH and LNR values should be identified based on large, well-controlled, prospective studies.
authors.affiliation: Department of Surgery, School of Medicine, Kurume University, Fukuoka, Japan. yoshisg@med.kurume-u.ac.jp
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Akagi
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Adachi
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Kinugasa
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Oka
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Mizobe
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shirouzu
mesh_terms: D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000401:mortality* / Q000473:pathology; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate; D014481:United States / Q000453:epidemiology
keywords: Colorectal cancer; lymph node harvest; lymph node metastasis; lymph node ratio; population-based study; prospective study; review; survival