Prediction of Nonsentinel Lymph Node (NSLN) Metastasis in Breast Cancer Patients; The Usefulness of Isotope Counts for Sentinel Lymph Node (SLN) Classification

PURPOSE: The goal of this study was to identify a patient subgroup with a positive SLN where exposure to the morbidity and cost associated of an axillary lymph node dissection (ALND) is not required. To achieve this goal, we subdivided SLNs according to their isotope counts, and then assessed whether the number of positive SLNs and subdivided status were related to the axillary NSLN status. METHODS: During SLN biopsies, the ex vivo isotope counts were measured for each SLN. Each SLN was labeled as S1, S2 or S3, and so on, in descending count order. An SLN biopsy was performed until the isotope counts of the axilla equaled that of the background. If SLNs were positive, a completion ALND (cALND) was performed. The pathological report was also reviewed and analyzed. RESULTS: SLNs were successfully identified in 243 (99.6%) of 244 patients, with metastases in SLNs identified in 28.0% of patients. An SLN was the only positive lymph node in 52.9% (36/68) of patients, with a positive SLN followed by a cALND. NSLNs metastases were found in 32/68 cases (47.1%). The rate of NSLN metastasis was positively correlated with the number of positive SLN (P=0.017). In SLN positive patients, the NSLN metastasis rate was 60.9% (28/46) in patient with a tumor-harboring last-order SLN (SLN with least isotope counts), but only 18.2% (4/22) in patients with a tumor-free SLN (P=0.001). Similar results were found in patients with either two or more metastatic SLNs (P=0.023). CONCLUSION: In patients with a positive SLN, the number of metastatic SLNs and their isotope counts can be useful in the prediction of NSLNs metastasis. Further investigation will be necessary to confirm these results.

Prediction of additional axillary metastasis of breast cancer with positive sentinel lymph nodes / 한국유방암학회지

PURPOSE: Axillary lymph node dissection in breast cancer patients with positive sentinel lymph node (SLN) is accepted as a routine procedure. In a significant proportion of women with breast cancer, the SLN is the sole site of regional metastasis. These patients would not be expected to benefit from complete lymph node dissection. The purpose of this study is to determine which factors are associated with additional positive lymph nodes in the axilla of patients who have positive sentinel lymph nodes. METHODS: Between September 2001 and May 2005, we examined 135 cases where the patients underwent a breast conserving operation and a SLN biopsy. There were 34 patients with positive SLN. Univariate analysis was used to identify the clinicopathologic features in the SLN positive patients that can predict metastasis in the nonsentinel lymph nodes (NSLNs). RESULTS: Fifteen patients (44.1%) had metastasis in the NSLNs. There were significant differences in the location of tumors (p=0.018), the nodal status of each patient (p=0.001) and c-erbB2 protein expression (p =0.017) in NSLN metastasis as determined by univariate analysis. CONCLUSION: The location of the breast cancer, nodal status and c-erbB2 expression are of predictive value for NSLN involvement. We suggest that a full axillary lymph node dissection may be considered as a sparing treatment in these situations.