Impact of the axillary nodal status on sentinel node mapping in breast cancer and its relevance for technical proceeding

Objective. The aim of this study is to analyze whether the axillary status influences the lymphatic mapping procedure in malignant breast disease and whether clinically relevant consequences for the technique of Sentinel Node (SN) biopsy may be drawn from this information. Materials and methods. SN biopsy was performed in 150 consecutive patients using a combination of the radioguided and the blue-dye technique. Axillary status was compared with the number of detected nodes. In cases of numerous nodes with tracer uptake, the radioactivity of each radiolabeled node was measured separately in a dose calibrator. We analyzed whether an increased tracer uptake could possibly indicate a 'true' or 'dominant' SN. Blue dye uptake was registered and compared with radioactivity. The findings were related to the histologic results. Results. In patients with a positive axillary status, significantly more radiolabeled nodes were detected than in node negative patients (median 3 vs. 2; p < 0.001). In 54/86 patients with numerous SNs a 'dominant' node with at least twice the radioactivity than other marked nodes could be identified (62.8 %). From 26 cases with axillary involvement, 20 patients (76.9 %) were identified by the 'dominant' and the remaining six women (23.1 %) by others than the seemingly leading SN. Conclusion. Axillary lymph node involvement influences the drainage pattern in breast cancer. Patients with numerous SNs have an increased risk of axillary involvement. A high tracer uptake does not permit the identification of a 'true' SN. A lack of surgical accuracy may lead to pitfalls if the axilla is not screened carefully for all radioactive nodes.