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.
The NCCN recommendation is based on a 2004 clinical trial that determined older women didn't need radiation because the additional therapy did not change mastectomy rates.
Smith was just finishing his residency when the NCCN recommendation was made public. He set out in his new practice with every intention to apply the current guidelines. Then, over time he began to observe something interesting.
Smith noticed one of his patients who had met the guideline criteria, and for whom he had not recommended radiation therapy, had a recurrence a few years after her initial diagnosis, which required a mastectomy.
Meanwhile, another patient, who also met the criteria but opted for radiation therapy after suffering horrible side effects with drug therapy, remained cancer-free.
This got him thinking. Perhaps some older women actually did benefit from radiation therapy.
“What was particularly helpful about our study was that we identified some women that did benefit from radiation therapy and some who didn’t benefit at all consistent with the guidelines that say that radiation was not needed,” Smith said.
Women who did not benefit from radiation were women aged 75-79 and older whose tumors had not spread to the lymph nodes but whose tumors were also non-high grade, meaning they were not aggressive tumors when you look at them under a microscope.
“In contrast, we found that patients, regardless of their age, who had an aggressive-looking tumor (when looked at under a microscope) all seemed to benefit much more, now and in the future, from radiation than you would have guessed based on the guideline statement. Without radiation their risk of a recurrence was between 10 to 15 percent but only 1 to 5 percent if radiation was administered,” Smith said.
Women whose tumors are in the gray area should discuss with their doctor the pros ad cons of radiation therapy, he said.
He said that most patients do well with radiation therapy without a lot of side effects but there are still reasons not to opt for radiation.
"Older women particularly need to discuss with their physicians their projected life expectancy. If they have a lot of other medical problems and may pass away in a few years from other problems, they probably don’t need radiation. Radiation is more about giving a long-term benefit in lowering recurrence over the next 10 years,” he said.
As for whether the national guidelines will be updated because of his research, Smith humbly says he doesn’t know for sure.
“One of our co-authors on this paper is a representative from the National Comprehensive Cancer Network Breast Cancer guideline committee, so I think it may provide for some interesting discussion the next time this group convenes to discuss the guidelines,” he said.
Lynette Summerill is an award-winning writer and Scuba enthusiast living in San Diego, CA with her husband and two beach loving dogs. In addition to writing about cancer-related issues for EmpowHER, her work has been seen in newspapers and magazines around the world.
Sources:
”Effectiveness of radiation for prevention of mastectomy in older breast cancer patients treated with conservative surgery.” Jeffrey M. Albert, I-Wen Pan, Ya-Chen Tina Shih, Jing Jiang, Thomas A. Buchholz, Sharon H. Giordano, Benjamin D. Smith. Cancer, published early online 31 Aug 2012. DOI: 10.1002/cncr.27457. Abstract online at
http://onlinelibrary.wiley.com/doi/10.1002/cncr.27457/abstract
Interview with Dr. Benjamin Smith, Radiation Oncologist, University of Texas MD Anderson Cancer Center, 16 August 2012.
National Comprehensive Cancer Network. NCCN Guidelines, Version 2. 2012; Senior Adult Oncology. Accessed at: http://www.nccn.org (Requires free subscription).
Reviewed August 21, 2012
by Michele Blacksberg RN
Edited Jody Smith