Breast Conserving Surgeries not so Conservative

Breast cancer partial mastectomies often followed by additional surgeries

(RxWiki News) Partial mastectomies, also known as lumpectomies and breast-conserving therapy, are popular surgical choices for women with early stage breast cancers. A good chunk of these women, though, will go under the knife again.

About a quarter of women who have lumpectomies will have to have additional surgery to remove additional tissue. These operations are known as re-excisions, and there is some mystery about why so many women have to undergo them because no quality standards have been defined.

"Ask your surgeon how often he or she performs additional surgeries after lumpectomies."

In an effort to look at the statistics relating to re-excisions, Laurence E. McCahill, M.D., of the Richard J. Lacks Cancer Center, Van Andel Research Institute, and Michigan State University, and colleagues looked at the rates at various hospital settings and among surgeons.

"Currently, there are no readily identifiable quality measures that allow for meaningful comparisons of breast cancer surgical outcomes among treating surgeons and hospitals," the authors wrote in a report that appeared in the February 1, 2012 issue of JAMA.

The goal of partial mastectomies is to achieve adequate surgical margins (the space between normal tissue and the breast cancer) while optimizing the appearance of the breast.

When inadequate margins are achieved during the first operation, additional surgery is required.

The study involved 2,206 women (average age 62) with invasive breast cancer who were treated with a partial mastectomy at four  institutions.

Data from a variety of medical records were examined, and here's what researchers found:

  • 509 women (22.9 percent) had additional surgery on the affected breast.
  • Of these patients, 454 women had a single re-excision, 48 underwent 2 re-excisions, and 7 had three additional surgeries.
  • Among all the women who had breast-conserving therapy, 190 of them had a subsequent total mastectomy performed.
  • Positive margins (meaning cancer remained) that resulted in re-excision ranged from 73.7 to 93.5 percent among the institutions studied.

dailyRx asked breast cancer specialist and surgeon, Cary Kaufman, M.D., to comment on these findings. He said that consideration of a number of complex factors "which have continuous variability" go into the surgical equation. 

"These include issues such as age, patient’s desire to preserve their breasts rather than have a mastectomy, the size of the cancer, the degree of closeness to the margin, how much of the margin was involved at that close distance, the existence of associated pre-cancer (in-situ cancer) in the area, the ability to follow the patient over time using their mammogram to look for recurrence (dense mammogram vs. clear mammogram) and especially the patient’s feeling of wanting further surgery, to stop and have a mastectomy or to have no further surgery regardless of the results," Dr. Kaufman, medical director of Bellingham Regional Breast Center in Washington state, explained.

"There is much research trying to find a way to identify the woman who has a positive margin at the time of surgery to avoid re-excision. There is a new [experimental light source which can 'see' positive cells during the operation, which cuts in half the number of re-excisions (but doesn’t eliminate it).

"There are defects in surgical and radiological techniques that may be improved that will [also] lower re-excisions," Dr. Kaufman concluded.

In an accompanying editorial, Monica Morrow, M.D., of the Memorial Sloan-Kettering Cancer Center, pointed out, "There is no consensus among surgeons and radiation oncologists as to what constitutes an optimal negative margin width because the question has not been addressed in prospective randomized trials. The observational design used in the McCahill et al study is valuable for illuminating the nature of potential quality gaps but cannot be used to inform the validity of candidate quality measures."

This work was funded by a grant from the American Recovery and Reinvestment Act of 2009 by the National Institutes of Health.

No author reported any conflicts of interest.

Review Date: 
January 31, 2012