Subareolar injection may be more accurate than other techniques for sentinel lymph node biopsy in breast cancer

The aims of this study were to compare peritumoral injection of (99m)Tc-labeled albumin and subdermal injection of blue dye with subareolar (SA) injection of blue dye alone in terms of success of the sentinel lymph node identification rate, false negative (FN) rate, overall accuracy, and sensitivity of the two procedures.

From January 1999 to October 2002, 155 patients with localized breast cancer were treated. Patients were subdivided into two groups. In patients in group 1 (n = 115; January 1999 to December 2001), lymphoscintigraphy together with injection of vital dye was performed. In patients in group 2 (n = 40; January 2002 to October 2002), SA injection of blue dye alone was performed.

In patients in group 1, the overall successful identification rate was 94.8%. The success rate of identifying a sentinel lymph node by a combination of the two techniques was 95%. With blue dye alone, the successful identification rate was 94.6% in patients in group 1 (subdermal) and 97.5% in group 2 (SA). The FN rate was 9% in group 1 and 0% in group 2. The overall accuracy of lymphatic mapping was 97% in group 1 and 100% in group 2. Sensitivity was 91% in group 1 and 100% in group 2.

This study of dye-only injection into the SA plexus demonstrates a high sentinel node identification rate, absent FN rate, and rapid learning curve. On the basis of these findings, we propose that injections into the SA lymphatic plexus are the optimal way to perform dye-only lymphatic mapping of the breast.