title: [Influence of the number of removed axillary lymph nodes on the prognosis of node-negative primary breast cancer].
abstract: OBJECTIVE
  To analyze the relationship between the number of removed axillary lymph nodes and prognosis of axillary node-negative breast cancer.
  
  
  METHODS
  The clinicopathological data of 655 patients with breast cancer were analyzed retrospectively. The disease-free survival curves were generated according to the number of removed axillary lymph nodes using Kaplan-Meier plots. The correlation between the co-variables and rate of breast cancer-related events was analyzed using Cox model.
  
  
  RESULTS
  The overall five year-disease free survival rate of the 655 cases was 94.4%. The rate of patients with lymph node number ≤ 12 was 90.3%, and that of lymph node number > 12 was 96.5%, with a statistically significant difference (P = 0.009). Significantly less breast cancer-related events were observed in patients with lymph node number > 12 (15/426, 3.5%) than that in patients with lymph node number ≤ 12 (22/229, 9.6%) (P = 0.009).
  
  
  CONCLUSIONS
  When axillary node dissection is indicated, dissection of lymph nodes >12 leads to much less breast cancer-related events than that in patients with dissected lymph node ≤ 12. The more lymph nodes are dissected, the more accurate prognosis can be estimated.
authors.affiliation: Department of Breast Surgery, the First Affiliated Hospital, China Medical University, Shenyang 110001, China.
authors.forename: Hui-ying
authors.initials: HY
authors.lastname: Wang
authors.forename: Hui-ting
authors.initials: HT
authors.lastname: Dong
authors.forename: Qun
authors.initials: Q
authors.lastname: Liu
authors.forename: Peng
authors.initials: P
authors.lastname: Xing
authors.forename: Ji-guang
authors.initials: JG
authors.lastname: Li
mesh_terms: D000328:Adult; D001365:Axilla; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000473:pathology* / Q000601:surgery; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008408:Mastectomy / Q000379:methods; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D015996:Survival Rate