A study has found that fewer women are having more surgery after lumpectomy to remove early-stage breast cancer. The researchers who did the study believe this is because guidelines released in 2014 endorsed very narrow clean margins.
The study was published online on June 5, 2017 by the journal JAMA Oncology. Read the abstract of “Trends in Reoperation After Initial Lumpectomy for Breast Cancer: Addressing Overtreatment in Surgical Management.”
Lumpectomy followed by radiation therapy is generally considered to be as good as mastectomy for women diagnosed with early-stage breast cancer with an average risk of the cancer coming back (recurrence). Earlier research has shown that recurrence risk was about the same with either type of surgery.
During lumpectomy, your surgeon’s goal is to take out all the breast cancer, plus a rim of normal tissue around it. This is to be sure all the cancer has been removed.
The tumor and surrounding tissue is rolled in a special ink so that the outer edges, or margin, are clearly visible under a microscope.
During or after surgery, a pathologist looks at the tissue that’s been removed to make sure there are no cancer cells in the margin. A clear, negative, or clean margin means there are no cancer cells at the outer edge of tissue that was removed. A positive margin means that cancer cells come right out to the edge of the removed tissue and have ink on them. In some cases, a pathologist may classify the margins as close, which means that cancer cells are close to the edge of the healthy tissue, but not right at the edge and don’t have ink on them.
For many years, there were questions about how wide a clear margin should be. Some doctors wanted 2 millimeters or more of normal tissue between the edge of the cancer and the outer edge of the removed tissue. Other doctors believed that 1 mm of healthy tissue was fine. Still other doctors thought that a clear margin could be smaller than 1 mm.
Because of the controversy, about 25% of women who had lumpectomy had a re-excision, which is when a surgeon reopens the lumpectomy site to remove a larger margin of cancer-free tissue. More surgery usually means more discomfort and stress for a woman and can possibly lead to more complications or side effects.
To establish a standard for lumpectomy margins for stage I and stage II breast cancer, the American Society for Radiation Oncology and the Society of Surgical Oncology issued new guidelines in February 2014 saying that clear margins, no matter how small as long as there was no ink on the cancer tumor, should be the standard for lumpectomy surgery. The guidelines also say that wider margins don’t lower the risk of recurrence any more than narrower margins.
In the study reviewed here, researchers wanted to know if the 2014 guidelines were having an effect on rates of re-excision surgery after lumpectomy.
The researchers looked at the records of 3,729 women who had lumpectomy to treat stage I or stage II breast cancer between 2013 and 2015. In 98% of the records, the surgeon was identified and the researchers surveyed 488 of the surgeons about lumpectomy margins. The researchers also reviewed the pathology reports of all the women who had more surgery after lumpectomy.
The researchers found that from 2013 to 2015, rates of more surgery after initial lumpectomy went down by 16%. The number of women who had lumpectomy as their only surgery increased from 52% to 65% during the years of the study.
Of the 342 surgeons who responded to the survey, 69% endorsed a “no ink on the tumor” margin for hormone-receptor-positive breast cancer and 63% endorsed the same margin for hormone-receptor-negative breast cancer. Surgeons who treated more than 50 breast cancer cases per year were much more likely to endorse a “no ink on the tumor” margin compared to surgeons who treated 20 breast cancer cases or fewer per year.
If you’ve been diagnosed with early-stage breast cancer and are planning your treatment, you and your doctor will consider which type of surgery makes the most sense for you based on your unique situation. For many women, lumpectomy followed by radiation therapy is a good option and more attractive than mastectomy, both physically and emotionally. This study offers peace of mind that you likely won’t need more surgery after lumpectomy if you have clear margins, no matter how small the clear margins are.
For more information on lumpectomy, including margins, visit the Breastcancer.org Lumpectomy pages.