title: Factors predicting non-sentinel lymph node metastasis in T1-2 invasive breast cancer with 1-2 axillary sentinel lymph node metastases: Presentation of Ondokuz Mayis scoring system.
abstract: OBJECTIVE
  To evaluate the predicting factors for non-sentinel lymph node (SLN) metastases in T1-2 invasive breast cancer with 1-2 metastatic SLN that fully matched the ACOSOG Z0011 criteria. Also, to develop a scoring system to predict the risk of non-SLN metastasis and to discriminate the low-risk patients for omission of the axillary lymph node dissection (ALND) in this population.
  
  
  METHODS
  Two hundred and seven T1-2 invasive breast cancer patients with 1-2 metastatic SLN who underwent ALND at our Institution were included in the study. Independent factors predicting the non-SLN metastasis were found using logistic regression analysis, and a scoring system to predict the non-SLN metastasis was created.
  
  
  RESULTS
  Seventy (34%) out of 207 patients had non- SLN metastasis. Multivariate logistic regression analysis demonstrated that tumor size, presence of lymphovascular invasion (LVI), number of negative SLNs, and size of SLN metastasis were independent factors predicting non-SLN metastasis. There were 68 (33%) and 108 (52%) patients with a the score of ? 4 (predicted probability of ?10%) with a false negative rate (FNR) of 4.4%, and ?5 (predicted probability of ?15%) with a FNR of 7.4%, respectively. The area under the curve (AUC) value for the Ondokuz Mayis scoring system was 0.88 (95% CI 0.83-0.93).
  
  
  CONCLUSIONS
  The present Ondokuz Mayis model with an AUC of 0.88 showed excellent discrimination capacity to distinguish patients at low risk for positive non-SLN from high risk patients and could help spare ALND in an important portion of patients.
authors.affiliation: Department of General Surgery, Ondokuz Mayis School of Medicine, Samsun, Turkey.
authors.forename: Bekir
authors.initials: B
authors.lastname: Kuru
authors.forename: Yurdanur
authors.initials: Y
authors.lastname: Sullu
authors.forename: Savas
authors.initials: S
authors.lastname: Yuruker
authors.forename: Ilkay
authors.initials: I
authors.lastname: Koray Bayrak
authors.forename: Necati
authors.initials: N
authors.lastname: Ozen
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery; D003661:Decision Support Techniques; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D016015:Logistic Models; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness; D016017:Odds Ratio; D018579:Patient Selection; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D018570:Risk Assessment; D012307:Risk Factors; D000071036:Sentinel Lymph Node / Q000473:pathology; D021701:Sentinel Lymph Node Biopsy; D014421:Turkey; D019564:Unnecessary Procedures