Value of sentinel lymph node metastasis status in predicting the presence of residual disease in the non-sentinel lymph node of breast cancer patients

Abstract

To explore the value of sentinel lymph nodes (SLN) metastasis status in predicting the presence of residual disease in non-sentinel lymph nodes (nSLN) and the feasibility of avoiding or reducing the scope of axillary lymph node dissection (ALND) for patients with single positive SLN. A retrospective study was conducted for 2265 patients with invasive breast carcinomas undergoing sentinel lymph nodes biopsy (SLNB) at Shandong Cancer Hospital between November 1999 and December 2011. And 1228 patients with axillary dissection were screened and divided into 5 groups of (-), (1/n), (1/1), (n/N), (n/n) (n ≥ 2, N ≥ 3, N > n) according to the status of SLN metastasis. The nSLN metastasis rate of SLN(-), (1/n), (1/1), (n/N) and (n/n) groups was 11.8%(73/618), 25.2%(65/258), 49.6%(67/135), 48.4%(60/124)and 65.6%(61/93)respectively. A comparison of SLN(-), (1/n), (1/1), (n/N), and (n/n) groups of nSLN metastasis showed a significant difference (P = 0.000). The differences of nSLN metastasis between SLN(-) and other groups (including 1/n, 1/1, n/N, n/n group) were significant (P = 0.000). This difference was also significant between SLN (1/n) and other positive groups (include 1/1, n/N, n/n group) (P = 0.000), but not significant between SLN(1/1), (n/N) and (n/n) groups (P = 0.842, 0.017, 0.042 respectively, Chi-square segmentation). No significant difference existed between axillary lymph node metastasis on Level II and III of SLN 1/n group and SLN(-) group (P = 0.012, 0.570,χ(2) segmentation). The status of SLN metastasis is one of influencing factors for the nSLN metastasis of patients with invasive breast cancer. The possibility of non-sentinel lymph node involvement for patients with single SLN metastasis was smaller than that of other SLN-positive patients. It is safe for some SLN 1/n patients to undergo low lymph node dissection. But ALND is not avoided for patients with single positive SLN (SLN 1/n n ≥ 2). Their clinicopathological variables should be also considered.