July 12, 2012— -- Partial breast removal surgery to treat cancer is not likely to be a one-time operation, according to many breast cancer experts and a study released Thursday.
One in five women who opt for partial breast removal, or breast-conserving surgery, may need a second operation to remove more breast tissue, according to a study of more than 55,000 British women.
Repeat surgery rates may be slightly higher among American women -- about one in four -- according to a study published last February in the Journal of the American Medical Association.
Breast-conserving surgery, including lumpectomy and partial mastectomy, is a less radical form of cancer surgery that seeks to remove the localized tumor or cancerous tissue within the breast. Additional surgeries are often performed when the doctors find additional tumors, or if the disease has spread to nearby lymph nodes.
Regarding breast-conserving surgery as a one-time fix may lead some surgeons to remove too much breast tissue the first time, or even to overlook the need to perform additional surgery.
Instead, the goal for both patients and surgeons is to find the clear margins of the cancer, which may take more than one try, many experts said.
British researchers looked at data collected from the Hospital Episode Statistics database of more than 55,000 women ages 16 and older who underwent breast-conserving surgery between 2005 and 2008.
Twenty percent of the women underwent additional surgery, and 40 percent of those who had repeat surgeries underwent a mastectomy, according to the findings that were published Thursday in the British Medical Journal.
The women were nearly twice as likely to undergo additional surgery if the tumor was ductal carcinoma in situ, an early localized form of the cancer in which it may be harder to detect the boundaries of the disease.
"The only way to be guaranteed a single surgical procedure with breast cancer is to perform the largest operation we perform – mastectomy with complete auxillary lymph node removal," said Dr. Ben Anderson, director of the breast health clinic at the University of Washington.
Still, many experts said that despite the findings, they would not recommend mastectomy over lumpectomy or partial mastectomy.
"The breast cancer survival rates are no different between women who undergo lumpectomy followed by radiation versus women who undergo mastectomy," said Dr. Keith Amos, assistant professor of surgery at the University of North Carolina at Chapel Hill. "I counsel each patient before a lumpectomy that obtaining clear margins may require more than one operation."
Breast-conserving surgery is still considered the premiere option for many women who want to save their breasts, and many patients are warned about the possibility of additional surgeries before they consent, experts said.
"Some women might try with a large lesion to preserve their breasts, and may ask the surgeon to 'try' to get around the lesion," said Dr. James Brenner, chief of breast imaging at University of California at San Francisco.
Breast experts use magnetic resonance imaging to better predict the margins of the disease, and suggest using MRI can potentially decrease the chance of additional surgery. However, previous studies suggest that patients who get MRIs have higher rates of mastectomies.
The study did not analyze whether the use of MRI influenced whether patients underwent additional breast-conserving surgery or mastectomy.
Some surgeons use a "cavity shave margin" technique, taking a little extra tissue outside the margin of the tumor to avoid another surgery.
While some surgeons aim for a single surgery, repeat surgeries should not be a measure of whether the procedure was successful, experts said.
"It is important that patients don't assume that re-excision should be zero, and if it isn't, then mastectomy should be done," said Lillie Shockney, associate professor in the department of surgery, oncology and gynecology and obstetrics at the Johns Hopkins School of Medicine.
"Most re-excision rates are successful and don't and shouldn't require mastectomy either," said Shockney.