Localization of the sentinel lymph node in breast cancer by combined lymphoscintigraphy, blue dye and intraoperative gamma probe

Axillary lymph node status represents the most important prognostic factor in patients with operable breast cancer. A severe limitation of this techni que is the relatively high rate of false negative sentinel lymph nodes (>5% ), We studied 284 patients suffering from breast cancer; 264 had T-1 tumors (16 T-1a, 37 T-1b and 211 T-1c), while 20 had T-2 tumors. All patients und erwent lymphoscintigraphy 18-h before surgery. At surgery, 0.5 mL of patent blue violet was infected subdermally, and the sentinel lymph node (SN) was searched by gamma probe and by the dye method. The surgically isolated SN was processed for intraoperative and delayed examinations. The SN was successfully identified by the combined radioisotopic procedure and patent blue dye technique in 278/284 cases (97.9%). Analysis of the pre dictive value of the SN in relation to the status of the axillary lymph nod es was limited to 191 patients undergoing standard axillary dissection irre spective of the SN status. Overall, 63/191 (33%) identified SNs were metast atic, the SN alone being involved in 37/63 (58.7%) patients; a positive axi llary status with negative SN was found in 10/73 (13.7%) patients with meta static involvement. In T-1a-T-1b patients the SN turned out to be metastati c in 9/53 patients (17.0%). In 7/9 patients the SN was the only site of met astasis, while in 2/9 patients other axillary lymph nodes were found to be metastatic in addition to the SN. None of the 44 patients in whom the SN pr oved to be non-metastatic showed any metastatic involvement of other axilla ry lymph nodes. Our results demonstrate a good predictive value of SN biopsy in patients wi th breast cancer; the predictive Value was excellent in those subjects with nodules smaller than 1 cm.