Three models for predicting the risk of non-sentinel lymph node metastasis in Japanese breast cancer patients.

Background: Axillary lymph node dissection (ALND) is the standard procedure for breast cancer with sentinel lymph node (SLN) metastasis. However, additional nodal metastasis is occasionally detected (<40 % cases) during complete ALND in patients with SLN metastasis. Several models have been developed to predict the non-SLN status of patients with SLN involvement. We evaluated 3 of these mathematical models independently.

Patients And Methods: A retrospective review was performed for 102 consecutive breast cancer patients with positive SLN biopsy who underwent ALND. We evaluated the area under the receiver operating characteristic curve (AUC) to determine the predicted risk of non-SLN metastases by using 3 mathematical models (from Memorial Sloan-Kettering Cancer Center (MSKCC), Stanford University, and Cambridge University).

Results: Of the 102 patients who underwent SLN biopsy, 47 (46.0 %) had a positive non-sentinel axillary lymph node metastasis. The AUC values were 0.71, 0.65, and 0.62 for the MSKCC, Stanford, and Cambridge nomograms, respectively.

Conclusions: None of the 3 nomograms had reasonable predictive power for the Japanese population. However, these nomograms can help individualize the surgical treatment of patients with positive SLN when the likelihood of further axillary metastasis is low. Each nomogram has its own characteristics for prediction of the risk of non-SLN metastasis.