Dr. Boughey Discusses the Z11 Trial in Breast Cancer

Judy C. Boughey, MD, associate professor of surgery, director, Breast Surgical Oncology Training Program, Mayo Clinic, discusses implications for axillary radiation following review of the ACOSOG Z11 trial.

Boughey says the trial has left physicians with a big question. Data from the study suggested that the patients should not receive radiation directed towards the axilla, but no data was collected on how the patients were treated. This finding led some physicians to believe that some radiation oncologists may have radiated the axilla due to the low rate of recurrence seen in the trial, Boughey says. Definitively radiating the axilla would have been a protocol violation, but the procedures were not tracked well during the trial.

A recent study was presented in which ACOSOG researchers looked at radiation reports from the trial. Boughey says these results showed that the majority of patients were treated with standard tangents and not with definitive radiation to the axilla. In the study, 89% of patients received radiation to the breast and about 15% had definitive radiation to the supraclavicular area.

A small subset of 200 patients from the study showed no difference in the radiation field planning between the group that was randomized to sentinel node only and the group that underwent axillary lymph node dissection. Boughey says this is encouraging information, but it is too small of a group to provide a definitive answer.