Prediction of Additional Axillary Metastasis of Breast Cancer Following Sentinel Lymph Node Surgery

Abstract

Sentinel lymphadenectomy is a sensitive and specific procedure that has reduced the need for complete axillary lymph node dissections in patients with negative sentinel lymph nodes (SLNs). However, numerous studies have shown that SLN may be the only positive lymph node in 40 to 70% of cases. This study was therefore undertaken to determine if the characteristics of primary breast tumor or its metastasis in the SLN could predict the presence of residual disease in the nonsentinel lymph nodes (NSLNs) and thus allow for further reduction in axillary lymph node surgery. The SLN procedure was performed on 329 patients at our institution, of which 131 had positive SLNs and underwent further axillary surgery. Fifty-four patients had additional disease in the NSLNs, while in the remaining 77 cases, no residual disease was detected. The clinical and pathologic features of these cases were reviewed and statistical analysis was performed. Multivariate analysis determined two significant independent variables for prediction of residual disease in the axilla: the size of the metastatic tumor in SLNs and the presence of its extranodal extension. The mean tumor size in SLNs without residual disease in NSLNs was 0.4 cm. It was 1.1 cm in patients with additional NSLN metastasis. The positive predictive value in both instances is about 80%. The risk of NSLN involvement in patients with SLN tumors of < or = 0.4 cm was 21%. The risk was the same (21%) for patients with micrometastatic disease (< or = 0.2 cm) in SLNs. In these cases the residual disease in the NSLNs was also small. SLNs with metastatic deposits larger than 1.0 cm were likely to contain additional metastases in the NSLNs in 81% of cases. This increased to 100% if the primary carcinoma was larger than 5 cm, if it was poorly differentiated, or if it showed HER-2/neu gene amplification. The presence of an extranodal extension of SLN metastasis was an independent predictor of residual axillary disease and was associated with NSLN metastasis in 76% of cases. Primary tumor characteristics did not correlate with the incidence of NSLN metastasis in our series.

Clinical significance of sentinel lymph node isolated tumour cells in breast cancer

“…Further evidence in support of the clinical significance of SLN ITC has also been put forward by other authors [65][66][67].…”

Increased Sentinel Lymph Node Lymphangiogenesis is Associated with Nonsentinel Axillary Lymph Node Involvement in Breast Cancer Patients with a Positive Sentinel Node

“…The median number of nonsentinel axillary LNs resected was 13 (3 -29). Metastatic involvement of at least one nonsentinel axillary LN was found in 37 of 65 (56.9%) patients, with the median number of involved nonsentinel axillary LNs being 3 (range, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Neither the size of the primary tumor, nor Nottingham grade, nor estrogen receptor, progesterone receptor, or Her2 status, nor the involvement of more than one sentinel LN, were correlated with the presence of nonsentinel LN metastases.…”

“…The size of the sentinel LN metastasis has emerged as a most powerful independent predictor in several studies (3 -15). Furthermore, the number of involved sentinel LNs (3,4,7,10,11,16), extracapsular growth of the sentinel LN metastasis (3,6,15), the size of the primary tumor (7,9,10,13,14), and the presence of lymphovascular invasion (4,7,9,14,15) have also been associated with metastatic involvement of nonsentinel axillary LNs. Based on these factors and on other clinicopathologic variables, Van Zee et al developed a nomogram to predict the likelihood of additional nodal metastases in breast cancer patients with a positive sentinel node biopsy (17).…”

Proteomic Profiling of Primary Breast Cancer Predicts Axillary Lymph Node Metastasis

“…SLN biopsy has a low but measurable falsenegative rate. Furthermore, it provides no information about the presence of additional non-SLN metastasis, which may occur in 40% to 70% of cases (12)(13)(14). Newer, more accurate, and less invasive means of predicting ALN metastasis would greatly improve breast cancer patient management and quality of life.…”