The purpose of this study was to assess the radiotherapy fields being offered to women with a positive sentinel lymph node (SLN) who have not had axillary lymph node dissection (ALND), based on the American College of Surgeons Oncology Group Z11 results.

We conducted a postal survey, addressed to radiation oncologists specialising in breast cancer treatment. In total, 179 cancer centres were contacted. Three hypothetical case scenarios were presented. In each case, the patient is clinically node negative but has a positive SLN following breast-conserving surgery, without further ALND. Respondents were asked what radiotherapy fields they would treat with in each scenario.

We received responses from 90 radiation oncologists from 73 centres in 11 countries. In the three scenarios (low, intermediate and high risk of further lymph node involvement), standard tangential beams would be used by only 27, 12 and 7%, respectively; high tangential beams by 33, 18 and 13%; tangents with full axillary/supraclavicular irradiation by 26, 51 and 61%; the remaining 14, 19 and 19% would use a nomogram to aid their decision.

This survey describes the lack of consensus regarding the management of the axilla in patients with clinically node-negative breast cancer but a positive sentinel node and who have not had ALND.