Are the axillary lymph nodes treated by standard tangent breast fields?

Background And Objectives: With the increasing use of sentinel lymph node biopsy, a growing proportion of women with early-stage invasive breast cancer are undergoing breast conserving surgery without a formal axillary lymph node dissection. A frequent question raised is whether the level I-II axillary lymph nodes are treated with standard breast tangent fields. In an attempt to answer this question, surgical clips placed at the time of the level I-II axillary lymph node dissection were used as a surrogate for the location of the nodes and the simulator films for tangent fields of 45 patients were analyzed.