Patrick Borgen, MD, Chair of the Department of Surgery at Maimonides Medical Center, Brooklyn, New York, called these findings important and clinically relevant. “This study was an enormous undertaking, to review the detailed clinical records on 3,000 consecutive patients. It’s an amazing and well-done piece of work,” he told The ASCO Post. For him, the clinical message here is that for patients with ductal carcinoma in situ who are not receiving radiation, wider margins are better. 

“This is essentially a post-op discussion with the patient, after you have the pathology results and know the margin status,” Dr. Borgen said. “Dr. Van Zee showed that in the patient who is not going to be irradiated, taking more tissue so that you achieve 1-cm margins reduces local recurrences by up to 70%.... If you know you are going to radiate, the question still is whether we need to re-excise a close margin. In Dr. Van Zee’s study, the effect of margin width disappeared when radiation was added.”

Dr. Borgen anticipates that the forthcoming consensus conference report on local-regional management of ductal carcinoma in situ will help answer this question and others. “I think the work of this committee will change practices,” he predicted. “We want to stop unnecessarily removing tissue from a woman’s breast, in so far as it’s safe, and this new information will give us much needed direction.” ■

Disclosure: Dr. Borgen is on the speakers bureau for Genomic Health and Genentech.