Older women with early stage breast cancer who undergo a lumpectomy may prevent the need for a later mastectomy by undergoing radiation therapy, a new study has found.
For women ages 70 and older, whose disease has not spread to the lymph nodes and is estrogen receptor positive (ER+), the typical treatment is breast-sparing surgery followed by tamoxifen, a medicine that blocks estrogen.
These women are often advised to forego radiation therapy in accordance with current national guidelines.
But researchers at University of Texas MD Anderson Cancer Center in Houston have found contrary to the national guidelines, radiation therapy provides some of these women with a measurable risk reduction of needing a mastectomy later on.
The study, published early online August 13, 2012, in journal of the American Cancer Society Cancer looked at 7,000 women between ages 70 and 79 who met the definition for early stage breast cancer.
Those who also underwent radiation therapy lowered their risk for mastectomy to 3.2 percent a decade after their diagnosis, compared to women who did not undergo radiation. Women in the non-radiation group’s risk of mastectomy was measurably higher at 6.3 percent.
The study’s lead investigator, Dr. Benjamin Smith, a radiation oncologist and assistant professor at UT MD Anderson, said having a mastectomy during the 10-year follow up period would “really be indicating that their cancer had come back and they were receiving the surgery to treat recurrence of cancer.”
Early stage breast cancer is stage 1 breast cancer. This is where the tumor is 2 cm or less in size and has not spread to lymph nodes.
It is a common problem for older women. In fact, about half of all breast cancer diagnoses in the United States is for women age 65 and older.
Since the early 2000s the National Comprehensive Cancer Network (NCCN) has advised against recommending radiation therapy for women age 70 or older, with stage 1 ER+ breast cancer. Their guidelines state these women can omit radiation therapy and use endocrine therapy alone.