SAN ANTONIO – Women with breast cancer at more than one site can undergo breast-conserving therapy and still have local recurrence rates well under the acceptable threshold of risk, suggest the results of first prospective study of this issue.
The ACOSOG-Z11102 trial involved more than 200 women with primarily endocrine receptor–positive (ER+), human epidermal growth factor receptor 2–negative (HER2-) breast cancer and up to three disease foci, all of whom underwent lumpectomy with nodal staging followed by whole-breast irradiation, then systemic therapy at the oncologist’s discretion.
After 5 years of follow-up, just 3% of women experienced a local recurrence, with none having a local or distant recurrence and one dying of the disease.
The new findings were presented at the San Antonio Breast Cancer Symposium on Dec. 9.
“This study provides important information for clinicians to discuss with patients who have two or three foci of breast cancer in one breast, as it may allow more patients to consider breast-conserving therapy as an option,” said study presenter Judy C. Boughey, MD, chair of the division of breast and melanoma surgical oncology at the Mayo Clinic, Rochester, Minn.
“Lumpectomy with radiation therapy is often preferred to mastectomy, as it is a smaller operation with quicker recovery, resulting in better patient satisfaction and cosmetic outcomes,” Dr. Boughey said in a statement.
“We’ve all been anxiously awaiting the results of this trial,” Andrea V. Barrio, MD, associate attending surgeon, Memorial Sloan Kettering Cancer Center, New York, told this news organization. “We knew that in patients who have a single site tumor in the breast, that outcomes between lumpectomy and mastectomy are the same ... But none of those trials have enrolled women with multiple sites.”
“There were no prospective data out there telling us that doing two lumpectomies in the breast was safe, so a lot of times, women were getting mastectomy for these multiple tumors, even if women had two small tumors in the breast and could easily undergo a lumpectomy with a good cosmetic result,” she said.
“So this data provides very strong evidence that we can begin treating women with small tumors in the breast who can undergo lumpectomy with a good cosmetic results without needing a mastectomy,” Dr. Barrio continued. “From a long-term quality of life standpoint, this is a big deal for women moving forward who really want to keep their breasts.”
Dr. Barrio did highlight, however, that “not everybody routinely does MRI” in women with breast cancer, including her institution, although generally she feels that “our standard imaging has gotten better,” with screening ultrasound identifying more lesions than previously.
She also believes that the numbers of women in the study who did not receive MRI are too small to “draw any definitive conclusions.
“Personally, when I have a patient with multisite disease and I’m going to keep their breasts, that to me is one indication that I would consider an MRI, to make sure that I wasn’t missing intervening disease between the two sites – that there wasn’t something else that would change my mind about doing a two-site lumpectomy,” Dr. Barrio said.
Linda M. Pak, MD, a breast cancer surgeon and surgical oncologist at NYU Langone’s Breast Cancer Center, New York, who was not involved in the study, said that the new study provides “importation information regarding the oncologic safety” of lumpectomy.
These results are “exciting to see, as they provide important information that breast-conserving surgery is safe in these patients, and that we can now share the results of this study with patients when we discuss with them their surgical options.
“I hope this will make more breast surgeons and patients comfortable with this approach and that it will increase the use of breast conservation among these patients,” Dr. Pak said.