Evaluation of three scoring systems predicting non sentinel node metastasis in breast cancer patients with a positive sentinel node biopsy

Background: Completion axillary lymph node dissection (cALND), performed after a positive sentinel lymph node biopsy (SLNB) in breast cancer patients, often results in no additional positive nodes. Scoring systems have been published to aid in the prediction of nonsentinel node metastasis. Our purpose was to assess the validity of these scoring systems in our patient population. Methods: For 39 consecutive patients who underwent cALND after a positive SLNB, scores were calculated using retrospective patient data for each of the three scoring systems used. Receiver operating characteristics (ROC) curves were drawn, and the areas under the curves were calculated to assess the discriminative power of each system. Univariate analysis was performed to assess the predictability of individual patient and tumor characteristics. Results: Nonsentinel nodes were positive in 23 (59%) patients. The areas under the ROC curves were 0.63, 0.70, and 0.68, respectively. The proportion of sentinel nodes that were positive and the total number of sentinel nodes retrieved were the only individual predictors of nonsentinel node metastasis. Conclusions: Given the high incidence of retrieving no additional metastasis on cALND, individualized patient management according to risk is desirable. Scoring systems provide additional information regarding the likelihood of metastasis in nonsentinel nodes, but their predictability remains less than optimal. The use of scoring systems must be applied with caution until future studies provide a more accurate assessment of risk for patients with a positive SLNB.