Positive non-sentinel axillary lymph nodes in breast cancer with 1-2 sentinel lymph node metastases

Recent clinical trials have shown that sentinel lymph node biopsy (SLNB) alone without axillary lymph node dissection (ALND) can offer excellent regional control if there is sentinel lymph nodes (SLN) metastases to 1-2 nodes. This study aimed to explore the predictive factors for non-sentinel lymph node (NSLN) metastasis in breast cancer patients with 1-2 positive SLNs. Patients with breast cancer and 1-2 positive SLN admitted between March 2009 and March 2017 and who underwent ALND after SLN biopsy (SLNB) at Beijing Chaoyang Hospital were analyzed retrospectively. Factors influencing the status of NSLN were studied by univariate and multivariate analysis. Of 1125 patients, 147 patients had SLN metastasis (13.1%) and 119 patients (81.0%) had 1-2 positive SLNs. Among them, 42 patients (35.3%) had NSLN metastasis. The invasive tumor size (P <.001), histological grade (P =.011), lymphovascular invasion (LVI) (P =.006), and over-expression of HER2 (P =.025) significantly correlated with non-SLN metastasis by univariate analysis. LVI (LVI) (P =.007; OR: 4.130; 95% confidence interval [CI]: 1.465–11.641), invasive tumor size (P <.001; OR: 7.176; 95% CI: 2.710–19.002), and HER2 over-expression (P =.006; OR: 5.489; 95% CI: 1.635–18.428) were independently associated with NSLN metastasis by the Logistic regression model. The ROC analysis identified a cut-off point of 26 mm of tumor size (area under the receiver operating characteristic [ROC] curve [AUC] 0.712, CI: 0.614–0.811) was useful for dividing patients with positive SLN (1-2 nodes) into non-SLN-positive and non-SLN-negative groups. For 1-2 positive SLNs of breast cancer, LVI, large invasive tumor size, and HER2 over-expression are independent factors affecting NSLN metastases.