LAS VEGAS – According to recent guidelines, no ink on tumor is the right surgical margin for early stage invasive breast cancer and 2 mm is the right lumpectomy margin for ductal carcinoma in situ (DCIS) treated with whole breast radiation. But, what do you do when invasive carcinoma is associated with DCIS?
It’s a common question for breast surgeons. Monica Morrow, MD, chief of breast surgery at Memorial Sloan-Kettering Cancer Center in New York City, explained how to handle the situation in a video interview at the annual meeting of the American Society of Breast Surgeons.
She was the senior author on the 2014 invasive breast cancer guidelines and the lead author on the 2016 DCIS guidelines, both of which were consensus statements on surgical margins from the Society of Surgical Oncology and other groups (Ann Surg Oncol. 2014 Mar;21[3]:704-16; Ann Surg Oncol. 2016 Nov;23[12]:3801-10).
Dr. Morrow explained the thinking behind the guidelines and how to apply them to mixed lesions and other clinical scenarios, as well as their limitations and what remains to be determined. A key point is that a margin less than 2 mm is not by itself an indication for mastectomy in DCIS.