Clinical Significance of Preoperative Lymphoscintigraphy for Sentinel Lymph Node Biopsy in Breast Cancer

Background: Lymphoscintigraphy (LSG) has been widely used as an additional modality to sentinel lymph node biopsy (SLNB) using isotope. However, the significance of the number of LSG-visualized axillary nodes has not been fully understood. We analyzed this and discussed its potential as a modality to complement SLNB. Methods: Ninety-one breasts and axillary lymph nodal status were evaluated retrospectively. All patients were examined by LSG using isotope and subsequently by SLNB. Results: Nine patients (9.9%) had no LSG-visualized axillary node, while 61 patients (67.0%) had only 1 node, and 21 patients (23.1%) had multiple nodes. Overall, sentinel lymph node (SLN) identification rate was 96.7%, and the mean number of removed SLNs was 1.5 nodes per patient. In patients with nonvisualized nodes, 66.7% of SLNs were successfully identified, while 100% of SLNs were identified in those with LSG-visualized nodes. Compared with patients with less than one visualized node, significantly more SLNs were removed in patients with multiple visualized nodes. The number of LSG-visualized nodes correlated with that of metastatic nodes. Conclusions: Preoperative LSG is effective in evaluating SLN status, and the LSG status could be associated with the number of dissected SLN. Moreover, the results of LSG potentially reflect the histological nodal status.