Breast Cancer Surgery Rules Are Called Unclear

Nearly half of women who had lumpectomies for breast cancer had second operations they may not have needed because surgeons have been unable to agree on guidelines for the most common operation for breast cancer, a new study finds. It also hints that some women who might benefit from further surgery may be missing out on it.

Rates of repeat surgery can vary widely by doctor, from zero percent to 70 percent, according to the study.

The additional operations are done when pathology reports on tumor specimens suggest that the first operation may have left behind some cancer cells. But surgeons differ when it comes to interpreting those reports.

Such uncertainty about a cancer operation that has been in use for 30 years is “a shame,” said Dr. Laurence E. McCahill, the first author of the study and a surgeon and assistant director of the Lacks Cancer Center in Grand Rapids, Mich. Dr. Monica Morrow, the chief of breast surgery at Memorial Sloan-Kettering Cancer Center in New York, said the study and attention from the public might help push professional groups to develop guidelines for surgeons. The details of surgery are not regulated, but surgeons generally follow expert advice.

“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,” Dr. Morrow said.

Dr. McCahill’s study, published online Tuesday by The Journal of the American Medical Association, is based on the medical records of 2,206 women who had lumpectomies at one of four hospitals in different parts of the country. Over all, 22.9 percent had more than one operation.

Nearly half of the repeat operations were done in women whose pathology reports did not indicate that any stray cancer cells had been left behind, meaning that the operations probably did not help the patients. In more disturbing findings, 14 percent of patients who did have evidence of cancer left behind did not have another operation, for unknown reasons.

Rates of repeat surgery varied by surgeon, and by hospital, from 1.7 percent to 20.9 percent. Differences in the patients did not account for most of the variation, though very thin women, who tend to have small breasts, were more likely to need second operations. Surgeons say that is because they try to remove as little tissue as possible from small breasts for cosmetic reasons.

“The number of operations women undergo definitely depends on where you’re treated, and even to a greater level on which surgeon you see,” Dr. McCahill said. “We put the math behind it and said, this is a lot of second operations that maybe don’t make a difference.”

Dr. McCahill said that such high repeat operation rates did not occur in other types of cancer surgery, in part because surgeons are not trying to spare tissue for cosmetic reasons as they are in lumpectomy.