Repeat breast cancer surgery rates vary widely: Why?

Reality: Survival rates are about the same for women who have mastectomies and for women who choose the breast-conserving option of removing only part of the breast and following the surgery with radiation treatments. However, there are some cases - such as with extensive DCIS disease, the presence of BRCA gene mutations, or particularly large tumors - when lumpectomy and radiation may not be an appropriate treatment option. More from How to help a loved one cope with breast cancer

(CBS) One in four breast cancer patients who have partial mastectomies get called back for more surgery, according to a new study.

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The observational study - published in the Feb. 1 issue of the Journal of the American Medical Association - examined the outcomes of breast cancer surgeries in women from four institutions and three health plans. Researchers looked specifically at reexcision rates following partial mastectomies.

What did they find? A lot of variety among institutions and surgeons. Of the 2,206 women studied who underwent partial mastectomies, 454 patients had another surgery, 48 had two more, and seven women had three reexcisions.

Reexcisions are performed if doctors believe there is still cancerous tissue left behind after the initial surgery. Doctors typically aim for a "clean margin" where there are no cancer cells in the tissue surrounding where the tumor is removed. The data did not show a connection between any discernable patient characteristics and rate of reexcision. The study showed 48 percent of women with a clean margin within one millimeter around the tumor had additional partial mastectomies. Twenty percent had a margin of up to two millimeters and were still re-operated on, and rates varied greatly among surgeons.

"A partial mastectomy is one of the most commonly performed cancer operations in the United States," Dr. Laurence McCahill, a surgeon with Michigan State University and director of surgical oncology at The Lacks Cancer Center, said in a written statement. "Currently, there are no readily identifiable quality measures that allow for meaningful comparisons of breast cancer surgical outcomes among surgeons and hospitals.

According to the study, "there remains a lack of standardization regarding [the application of partial mastectomy reexcisions] among surgeons performing breast cancer surgery."

"The wide level of unexplained clinical variation itself represents a potential barrier to high-quality and cost-effective care of patients with breast cancer," McCahill said.

Dr. Monica Morrow, chief of breast surgery at Memorial Sloan-Kettering Cancer Center in New York, told The New York Times, "It is getting to be the time for leaders in radiation oncology and surgery to get together and make a consensus statement that could help to guide their membership."