| Background:The metastatic status of axillary lymph nodes is an important reference for the evaluation of prognosis and adjuvant treatment in breast cancer patients,and sentinel lymph node biopsy(SLNB)is a milestone in the field of breast surgery in the 1990 s.A number of studies have shown that SLNB can accurately predict axillary lymph node metastasis.If there is no tumor cell metastasis in the sentinel lymph node(SLN),axillary lymph node dissection(ALND)can be avoided.ALND is still a routine treatment for patients with metastatic cancer cells in SLN.However,retrospective studies have shown that 40% to 60% of SLN-positive ALND patients do not have non-sentinel lymph node(NSLN)metastases,so this group of patients can theoretically avoid ALND.Therefore,many scholars have explored in this field,hoping to find the risk factors of NSLN metastasis,so as to screen out patients with low possibility of NSLN metastasis to exempt ALND.The most classical predictor of NSLN metastasis in SLN-positive breast cancer patients is the predictive model proposed by researchers at the Memorial Sloan-Kettering Cancer Center(MSKKCC)in the United States.Objective:To explore which clinicopathological features of SLN-positive breast cancer patients can predict NSLN metastasis.To validate and evaluate the clinical application value of MSKCC-established NSLN metastasis prediction model in early breast cancer patients in our study center.Methods:We used retrospective analysis of clinicopathological data of patients from the Department of Breast Surgery,Second Hospital of Jilin University from December 2011 to August 2018,who received successful SLNB with a metastasis positive results,followed by ALND.Chi-square test、 Rank sum test and Logistic regression analysis were used to analyze the correlation between clinicopathologic characteristics and NSLN metastasis;MSKCC nomogram was used to estimate probability of NSLN involvement,and the predictive accuracy was assessed by the area under the receiver-operator characteristic(ROC)curve.Results:A total of 395 patients received SLNB in this study,including 81 patients with SLN who had metastases and further ALND.Univariate analysis showed that NSLN metastasis was associated with positive SLN number(p=0.008),tumor diameter(p=0.014)and vascular invasion(p=0.003).And age,lymph node metastatic size,number of negative SLN,histological type,histological grade,multiple lesions,molecular typing,estrogen receptor(ER)status,progesterone receptor(PR)status,human epidermal growth factor receptor 2(HER-2)and Ki67 expression status are not related with NSLN metastasis.Multivariate analysis confirmed that the number of positive SLN(OR=2.675,P=0.006)and tumor diameter(OR=2.631,P=0.019)were independent influencing factors of NSLN metastasis.The MSKCC nomogram presented a ROC value of 0.720.Patients with predictive values lower than 10%(8/61,13.1%)have a frequency of NSLN metastasis of 37.5%(3/8).Conclusion:1.Tumor size and the number of positive SLN are independent risk factors for NSLN metastasis in SLN-positive breast cancer patients.Patients may avoid ALND who has no more than two SLN-positive and with a tumor size of 1 cm or less.2.MSKCC has poor accuracy in predicting NSLN status of this population.So it should be relatively cautious to use it as a reference for ALND. |
