Frozen section analysis during breast cancer lumpectomies spared patients the need for a repeat lumpectomy in about 96% of cases, according to a new study. This success rate is much higher than the national rate of about 87%.
This study, published in the journal Surgery (2014; doi:10.1016/j.surg.2014.03/025) and performed at Mayo Clinic in Rochester, Minnesota, found that 13.2% of patients nationally who had breast cancer lumpectomy had to return to the operating room within a month of their initial surgery, compared to 3.6% at Mayo in Rochester. The technique of frozen section analysis was used at Mayo to test excised tissue for cancer while the patients were still on the operating table.
In breast cancer lumpectomies, surgeons remove tumors with a small amount of normal tissue around them to help ensure they excised all of the cancer. This is known as obtaining “clean” or “negative” margins.
During surgery at the Mayo Clinic, that tissue is transferred from the operating room to a nearby pathology lab, where the edges around the lumpectomy are shaved and each sample is frozen and reviewed under a microscope by a pathologist, all within minutes, while the patient is still anesthetized. The pathologist immediately gives the surgeon the results, so the surgeon knows whether the lumpectomy is complete or there is still cancerous tissue to remove, and at which margin, before the operation concludes.
Mayo Clinic remains one of the only medical centers in the United States to perform frozen section analysis, and its process is unique, including use of a Mayo-modified microtome to freeze tissue so the pathologist can get a 360-degree view around the lumpectomy cavity.
“This intense pathological evaluation with the use of frozen section of the margins while the patient is asleep really drops down the re-excision rate,” said first author Judy Boughey, MD, a breast surgeon in the Mayo Clinic Cancer Center. “Achieving negative margins in one operation has a huge impact on the patient’s satisfaction, decreases time away from work, time traveling back and forth to hospital appointments, and the financial cost to the patient, the insurance company, and the hospital for a second operation.”
Unlike mastectomy, a breast cancer lumpectomy typically preserves enough breast tissue to achieve an acceptable cosmetic result. Most women diagnosed with breast cancer have a choice between a lumpectomy and a mastectomy. However, women who have a lumpectomy and later learn another operation is needed to obtain negative margins may decide to get a mastectomy at that point, Boughey stated.