Rationale for superficial injection techniques in lymphatic mapping in breast cancer patients.

One of the most avidly debated issues in lymphatic mapping is where the tracers are best deposited in patients with breast cancer. The four superficial approaches are easy to perform and have several other distinct advantages. They are based on the hypothesis that the entire breast parenchyma and the overlying skin drain to a common node in the axilla because of their common embryological origin. Evidence is presented that casts doubt upon the correctness of this assumption. Tracer administration close to the tumor site appears to be the safest approach for the time being. Excellent results can be obtained with this latter approach, despite the fact that it is technically more demanding.