Late Breaking News
Debate Over Breast Cancer Screening for Older Women Continues at VA
By Annette Boyle
SAN FRANCISCO - A handful of new studies on the harms and benefits of mammography screening for older women give VHA physicians more information but no easy answers.
The rapidly rising number of female veterans makes the debate over who and when to screen is a matter of daily significance for primary care physicians in the VA, which currently screens 87% of eligible women, a substantially higher percentage than the 71% screened in the private sector.
The higher screening rates are not associated with improved outcomes, however. Female veterans are diagnosed with breast cancer at an average age of 56, compared with age 61 in women who never served in the military, and they have lower five-year survival rates at every stage compared with nonveteran women in the Surveillance Epidemiology and End Results (SEER) database.1
The VA follows the recommendations of the U.S. Preventive Services Task Force on breast cancer screening and encourages women between the ages of 50 and 75 to have a mammogram every two years.
“Women between the ages of 40 and 50 and those over the age of 75 should talk with their providers about the risks and benefits of having mammograms and make a decision based on their individual risk factors,” according to the VA.
Life Expectancy, Not Age
For older women, that discussion and the risk analysis that goes with it might be complicated.
“The one-size-fits-all approach to medical care based on somebody’s age really doesn’t work in a very heterogeneous elderly population,” said Louise Walter, MD, a geriatrician at the San Francisco Veterans Affairs Medical Center and interim chief of the Division of Geriatrics, University of California San Francisco.
“It’s not so much age that determines when you should stop screening for breast cancer; it’s more thinking about the risks and benefits and how that’s affected by other types of medical conditions, as well as patient preferences,” Walter told U.S. Medicine.
According to a recent article Walter co-authored in the British Medical Journal, the potential benefits might not outweigh the possible harms for patients who have a life expectancy of 10 years or less. Researchers found that more than 10 years were required before one death was prevented for 1,000 women screened. 2
Understanding the Harms
Each year, about 10% of women will have a false positive result from mammography and 1% will have a biopsy, according to Walter and her colleagues. One in 1,000 will be diagnosed with a breast cancer that would remain asymptomatic for her lifetime, yet have the risks associated with unnecessary surgery, radiation or other treatments.
Consequently, the authors conclude that “patients with a life expectancy greater than 10 years should be encouraged to undergo screening,” while those with a life expectancy of less than three to five years “should be discouraged from screening, since the potential risks probably outweigh the small probability of benefit.”
As women age, the risks rise, according to Karla Kerlikowske, director of the Women Veterans’ Comprehensive Health Center at the San Francisco VAMC. Among women over age 65 who have annual mammograms, “If you live long enough to have that 10-year window of benefit, the cumulative harms that go with that are around 60% for experiencing a false positive recall and 15% for a false positive biopsy recommendation.”
The harm from false positives extends beyond a few days of anxiety, according a new study in the Annals of Family Medicine.
“Six months after final diagnosis, women with false positive findings reported changes in existential values and inner calmness as great as those reported by women with a diagnosis of breast cancer,” reported the authors. Even “three years after being declared free of cancer, women with false positive results consistently reported greater negative psychosocial consequences compared with women who had normal findings.”3
Biopsies also have potential for long-term harm, noted Kerlikowske. “One of my colleagues showed that the biopsies create these little scars, and those increase the risk of false positives in subsequent mammograms, so it becomes a vicious little circle.”
Stop Screening at 75?
“Overdiagnosis also rises sharply after age 74,” added Kerlikowske, who co-authored a recent study on screening outcomes in mammography, published in the Journal of the National Cancer Institute.4
“We are overtreating all these people because we’ve identified lesions that would otherwise never become known. They have very indolent tumors that won’t affect their survival, and the harm is pretty overwhelming,” Kerlikowske told U.S. Medicine. “Over age 74, there are so many competing risks that even if you screened, the patient wouldn’t live long enough to have a benefit.”
Walter and other researchers disagree.
“We don’t have data on women over age 74, because they haven’t been included in trials. The U.S. Preventive Services Task Force guidelines make no recommendation — they give it a grade I, meaning there is insufficient evidence to recommend for or against screening after age 75,” Walter said.
“It needs to be a more individualized decision when you have older patients,” she added. “We have to think about why is it that they would not benefit. Many 74 year olds are going to live another 20 years, but it would be crazy to screen a woman in a nursing home with dementia.”
Her view gained support from a presentation at the American Association for Cancer Research (AACR) Annual Meeting 2013, which found that for women age 75 and older, a five-year or longer interval between the last mammogram and the date of breast cancer diagnosis tripled the risk of dying from breast cancer compared with those whose breast cancer was diagnosed six months to a year after their last mammogram. 5
While those researchers encouraged physicians to continue mammography screening for older women, they noted multiple possible explanations for the results.
“It is possible that the differences in the relationship between screening interval and mortality in older vs. younger women may be related to the more aggressive nature of the tumors in younger women, which might obliterate the effects of more screening. Other reasons may include differences in cancer treatment,” said Michael Simon, MD, MPH, professor of internal medicine and oncology at Wayne State University School of Medicine in Detroit.
In keeping with the contradictory data and opinions seen in other aspects of the breast cancer screening debate, Kerlikowske and her colleagues found that age, screening interval and comorbidity had no statistical association with adverse tumor characteristics.
1 Thota R, Subbiah S, Tashi T, Aldoss I. Breast cancer in female veteran population: Survival analysis from VA cancer registry. ASCO 2010 Breast Cancer Symposium.
2 Lee SJ, Boscardin WJ, Stijacic-Cenzer I, Conell-Price J, O’Brien S, Walter L. Time lag to benefit after screening for breast and colorectal cancer: meta-analysis of survival data from the United States, Sweden, United Kingdom, and Denmark. BMJ. 2013;346:e8441.
3 Brodersen J, Siersma VD. Long-term psychosocial consequences of false-positive screening mammography. Ann Fam Med. March/April 2013. 11(2):106-115.
4 Braithwaite D, Zhu W, Hubbard RA, O’Meara ES, Miglioretti DL, et al. Screening outcomes in older US women undergoing multiple mammograms in community practice: Does interval, age, or comorbidity score affect tumor characteristics or false positive rates? J Natl Cancer Inst. 2013;105:334-341.
5 Simon MS, Wassertheil-Smoller S, Thomson C, Ray RM, Hubell FA, Lane D, et al. Mammography interval and breast cancer mortality in the Women’s Health Initiative. Abstract #157. AACR Annual Meeting 2013.
Related Women's Health Articles
- Survey Seeks to Establish Sexual Trauma Scale Unique to Military
- New Instruction on How DoD Providers Should Care for Sexual-Assault Victims
- Debate Over Breast Cancer Screening for Older Women Continues at VA
- Military Responds to High Rates of STIs in Active-Duty Female Servicemembers
- DoD Now Will Fund Abortions in Pregnancies from Rape, Incest
- Is Getting Disability Benefits Too Difficult for Military Sexual Assault Victims?
- VA Should Fund Fertility Treatments for Injured Servicemembers, Spouses, According to New Bill
- Don't Call Me 'Mister': Report Says VA Needs Cultural Change in Women's Care
- VA Seeks to Gather More Information on Women Veterans to Improve Care
- Enhanced Court-Martial Process Targets Sexual Predators in Military