For many women with breast cancer, the choice between lumpectomy and mastectomy is difficult and confusing. Lumpectomy, or the removal of the "lump" of cancer, is considered a safe and acceptable option for small breast tumors, those that are roughly 2 cm or less in diameter. A 2 cm tumor is equivalent to about three-quarters of an inch. Women with tumors larger than 2 cm often are advised that it might be safer in the long term to have a mastectomy, which is complete removal of the breast tissue.
However, a new European study shows that even after more than 10 years, women who'd had tumors larger than 2 cm and had had a lumpectomy or a mastectomy were still alive in similar proportions regardless of which procedure they'd chosen. Some women in the study had tumors as large as 5 cm, which is about 2 inches.
"I would say 5 cm is certainly the maximum, but [for tumors less than 5 cm] if you are treated with mastectomy or breast-conserving therapy, the results are equal for at least 13.4 years," says Harry Bartelink, MD, PhD, an author of the study, which was published in a recent issue of the Journal of the National Cancer Institute.
The study, which began in 1980, included 420 British, Dutch, Belgian, and South African women who had mastectomies and 448 women from those same countries who had breast-conserving lumpectomy. Tumors ranged in size from 2 cm to 5 cm.
After more than 10 years, 66% of women who had mastectomy and 65% who had lumpectomy were still alive and well, reports Bartelink, who is with the Netherlands Cancer Institute in Amsterdam. He says survival rates for women in the study were similar whether their tumor was 2 cm or 5 cm.
The one major difference between the two groups was the rate of "local" cancer recurrence in or near the site of the original tumor. Approximately 12% of women who had a mastectomy had the cancer come back in or near the original tumor's site, compared with 20% of women who had a lumpectomy. Bartelink says the 20% rate is higher than would be expected if the study was done today, because techniques have improved since the early 1980s, when the women in the study were treated.
He tells WebMD that keeping track of what happens to these patients a decade or more after their breast cancer is important because it provides more proof that lumpectomy is safe.
This study adds to a large body of medical data showing that lumpectomy is not associated with higher rates of death than mastectomy, according to Stephen B. Edge, MD, who reviewed the study for WebMD.
"It's important that we continue to see what the information from these trials shows," he tells WebMD. "More and more people are alive and well many years after breast cancer, and it's important for us to be able to tell them what the long-term outlook is."
Edge, who is chief of breast surgery at Roswell Park Cancer Institute in Buffalo, N.Y., says the European study agrees with a large American trial that included women with tumors as large as 4 cm who were offered lumpectomy.
"Basically, people have been willing to do lumpectomies up to 4-5 cm without much hesitation as long as the lesion is small enough in relation to the size of the breast," he says. For example, a woman with a large breast might be more of a candidate for lumpectomy to remove a larger tumor than a smaller-breasted woman, in whom removal of a large amount of tissue might leave a cosmetically unacceptable result. In addition to the actual tumor, doctors also must remove tissue around the tumor that may contain microscopic cancer cells, so the actual size of what needs to be removed can vary.
But overall, Edge says the findings are encouraging for women faced with a difficult decision. "This study further supports the statement that if you are appropriately treated with lumpectomy, you are not in any way jeopardizing your life by preserving your breast."
For more information from WebMD, visit our Disease and Conditions Breast Cancer page.