Axillary evaluation in ductal cancer in situ of the breast: challenging the diagnostic accuracy of clinical practice guidelines.

The decision whether to operate on the axilla in women with a diagnosis of ductal cancer in situ (DCIS) is based on the risk of an undiagnosed underlying invasive cancer and on the concern that resection of the breast will not allow for accurate axillary mapping afterwards. Guidelines stem from older knowledge and are heterogeneous. In this study, different breast cancer guidelines were tested in a patient cohort from the SentiNot prospective trial for uniformity of interpretation and diagnostic accuracy. Results show that guidelines did not allow for easy and uniform interpretation and had the predictive ability of the toss of a coin. This suggests that guidelines regarding the need of axillary evaluation in patients operated for DCIS need to be revised and that techniques that will address the conundrum should be developed.