title: Ki-67 labeling: a more sensitive indicator of malignant phenotype than mitotic count or tumor size?
abstract: OBJECTIVE
  The Ki-67 index has been incorporated into The World Health Organization's classification system of pancreatic neuroendocrine tumors. However, pathologists continue to question the utility of Ki-67 index over that of mitotic count as an indicator of proliferative activity. The intent of the current study is to compare K-i67 index with tumor size and mitotic rate for the association of each with lymph node metastasis and survival.
  
  
  METHODS
  The current study is a review of 24 patients with pancreatic neuroendocrine tumors.
  
  
  RESULTS
  Regional LNM were present in 100% of tumors with Ki-67 index >10%, while only 25% of tumors with <10% Ki-67 had LNM (P = 0.003). No tumors <2 cm had >10% Ki-67 labeling. Of patients with tumors showing ≥ 10% Ki-67 labeling, 80% died during the observation period of this study, while during the same time period, no patients with <10% Ki-67 labeling died.
  
  
  CONCLUSIONS
  Ki-67 index of >10% is a sensitive indicator of malignant behavior and mortality. Future advances in management of pNETs will require development of staging guidelines with higher predictive value. Inclusion of Ki-67 labeling >10% as an indicator of aggressive disease may contribute to such improvements.
authors.affiliation: Department of HPB Surgery, Methodist Dallas Medical Center, Dallas, Texas 75208, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Lowe
authors.forename: Amit
authors.initials: A
authors.lastname: Khithani
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Liu
authors.forename: Tanyss
authors.initials: T
authors.lastname: Winston
authors.forename: Derrick
authors.initials: D
authors.lastname: Christian
authors.forename: Joe
authors.initials: J
authors.lastname: Saad
authors.forename: Dhiresh Rohan
authors.initials: DR
authors.lastname: Jeyarajah
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D018358:Neuroendocrine Tumors / Q000737:chemistry / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000737:chemistry / Q000473:pathology*; D010641:Phenotype
chemical_list: D019394:Ki-67 Antigen