Risk factors for sentinel lymph node metastasis and validation study of the MSKCC nomogram in breast cancer patients

To evaluate the risk factors for sentinel lymph node metastasis and validate the value of the Memorial Sloan-Kettering Cancer Center nomogram for the prediction of sentinel lymph node metastasis in breast cancer patients.

A sentinel lymph node biopsy database containing 1227 consecutive breast cancer patients (416 patients with at least one positive sentinel lymph node) was retrospectively analyzed. The predictive value of the Memorial Sloan-Kettering Cancer Center nomogram was calculated by the trend line and the area under the receiver-operator characteristic curve. Meanwhile, predictors for sentinel lymph node metastasis were also evaluated.

Tumor size, histological grade, lymphovascular invasion, mulifocality, estrogen receptor and progesterone receptor status were significant independent predictors for sentinel lymph node metastasis (all P<0.01). The Memorial Sloan-Kettering Cancer Center nomogram presented an area under the receiver-operator characteristic curve value of 0.730. Patients with predictive value<16% had a frequency of sentinel lymph node metastasis of 0.9%. Those with values larger than 70% had a frequency of 96.2%.

The risk factors for sentinel lymph node metastasis in our study were consistent with those in the Memorial Sloan-Kettering Cancer Center nomogram. The Memorial Sloan-Kettering Cancer Center nomogram is a useful tool that could accurately predict the probability of sentinel lymph node metastasis in our breast cancer patients. Axillary surgical staging might be avoided in patients with a predictive value of <16% and axillary lymph node dissection might be done directly in those with a predictive value >70%, while other patients should still accept sentinel lymph node biopsy.