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

Abstract

Objective To evaluate the risk factors for sentinel lymph node(SLN)metastasis,and assess the value of the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram in predicting SLN metastasis in breast cancer patients.Methods A sentinel lymph node biopsy(SLNB) database containing 1227 consecutive breast cancer patients(412 patients with a positive SLN)was retrospectively analyzed.The value of MSKCC nomogram was predicted by drawing the trend line and calculating the area under the curve(AUC) of receiver-operator characteristic(ROC). Meanwhile,the risk factors of SLN metastasis were evaluated. Results Tumor size,tumor location,histological grade,lymphovascular invasion,mulifocality,ER and PR status were correlated with SLN metastasis( all P ＜ 0.05 ).All the above factors but tumor location were significant independent predictors for SLN metastasis(all P ＜ 0.01 ).The MSKCC nomogram presented AUC value of 0.730 for ROC.Patients with predictive values lower than 16％ had the frequency of 0.9％ for SLN metastasis while patients with predictive values higher than 70％ had the frequency of 96.2％.Conclusions The risk factors of SLN metastasis in our study are consistent with those in MSKCC nomogram.MSKCC nomogram is a useful tool in predicting the probability of SLN metastasis for breast cancer patients.Axillary surgery can be avoided in patients with the predictive values lower than 16％,axillary lymph node dissection could be done in patients with the predictive values higher than 70％,and other patients should still undergo SLNB. Key words: Breast cancer; Sentinel lymph node; MSKCC nomogram; Prediction