A preliminary report shows that surgery that spares the breast in patients with a certain kind of early-stage breast cancer has better survival rates than mastectomy.
The study findings, reported Consumer Affairs, “defy the conventional belief that the two treatment interventions offer equal survival, and show the need to revisit some standards of breast cancer practice in the modern era, …”
Breast-conserving therapy (BCT), according to a paper presented at the Breast Cancer Symposium earlier this month, involved lumpectomy plus radiation for patients with early-stage, hormone receptor-positive breast cancer. Lumpectomy is the removal of only the mass with the tumor, not the whole breast (mastectomy). Hormone receptor-positive breast cancer (HR+) is when the cells have receptors for either estrogen or progesterone, which invites growth. Hormone receptor status is a primary factor in how a patient’s breast cancer is treated.
In the 1980s, according to Consumer Affairs, studies concluded that (BCT) and mastectomy were equal in terms of survival among women with early-stage breast cancer. But because those studies were conducted when not much was understood about breast cancer biology — for example, subtypes, how and where it recurs and its potential to metastasize, or spread beyond the original site — they don’t have much relevance in today’s more advanced cancer analysis.
As reported by MedPageToday.com, the study’s data and conclusions haven’t been published in a peer-reviewed journal, so they must be considered preliminary. And the five-year survival rate was significantly different between patients who had only a mastectomy or lumpectomy, regardless of their hormone receptor status.
Patients treated with BCT (lumpectomy plus radiation) showed an unadjusted five-year overall survival of 96 in 100. The rate for the mastectomy patients was 90 in 100. Among women who had no radiation, only breast-conserving surgery (BCS) the rate was 87 in 100.
Dr. Catherine Parker and her colleagues at the MD Anderson Cancer Center in Houston analyzed how the choice of treatment affects survival according to each tumor’s biology. The analysis involved 16,646 patients newly diagnosed with stage I breast cancer who were treated in 2004 and 2005.
More than 11,200 were treated by BCT, 3,587 by mastectomy and 1,845 by BCS. The mean age was 59 in the BCT subgroup, 62 in the mastectomy group and 66 in the BCS group. The follow-up period was nearly seven years.
Tumors were classified by hormone receptor status — HR+ was positive for receptors for estrogen, progesterone or both, and HR- was negative for both types of hormone receptors. The primary outcome was overall survival.
The study made two key points, according to Dr. Harold Burstein of the Dana-Farber Cancer Institute in Boston. One confirms many previous studies showing that in terms of survival, BCS is at least as effective as mastectomy. Two is that the combination of radiation and lumpectomy is very important for overall survival.
Burstein told MedPage Today that the second take-away "has been a controversial point. The benefits in some of the studies have been rather small.
"What's clear in this population-based study of thousands of women is that adding radiation therapy — even for the favorable-prognosis stage I breast cancers — helps women do better in terms of survival down the road."
We would add that any time you can avoid a more invasive procedure in favor of a less traumatic surgery, such as lumpectomy over mastectomy, you reduce your risk of complications, such as infection, and also the psychological fallout from losing part of your anatomy.
To learn more about breast cancer, see our backgrounder.