Newly issued mammography screening guidelines for breast cancer survivors aged 75 and older recommend discontinuing routine mammography for those with a life expectancy of less than 5 years and considering discontinuation of routine screening for those with a life expectancy between 5 and 10 years. Published in JAMA Oncology,1 the guidelines were not intended to be prescriptive, according to lead author Rachel A. Freedman, MD, MPH, but may offer clinicians support in discussions with older breast cancer survivors about whether or not to continue surveillance mammography.
“These guidelines are really meant for aging breast cancer survivors who have other medical conditions,” Dr. Freedman said in an interview with The ASCO Post. Dr. Freedman is Medical Director of the Dana-Farber Cancer Institute Cancer Care Collaborative, Boston, and Associate Professor of Medicine at Harvard Medical School. Many survivors may think mammography is “forever going to be beneficial for them,” Dr. Freedman continued. “But the truth is that we don’t know whether that is the case. There are many women who probably do not benefit from mammography at a certain point but still experience the harms or the downsides of mammography. Just informing women about this can be helpful.”
Rachel A. Freedman, MD, MPH
Applicable to All Practices
Following an extensive literature review of ipsilateral and contralateral breast cancer events among breast cancer survivors and the benefits and harms associated with mammography, a nationwide multidisciplinary panel worked together to develop the guidelines. The draft guidelines were then reviewed by clinician focus groups and members of the International Society for Geriatric Oncology (SIOG). “After reaching more than 95% consensus by panelists and SIOG members, the guidelines were finalized,” the panel reported.
As breast cancer survivors age, “they may transition away from medical oncology,” Dr. Freedman noted. “Many of them may be followed by primary care doctors or geriatric physicians. We thought it was important that these guidelines could apply to any practice, and so we included geriatricians, radiologists, primary care doctors, and nurses in our conversations,” as well as medical oncologists, surgeons, and patients.
Individualizing Decisions
“The standard recommendation for mammography in breast cancer survivors of all ages has been annual screening. There has been little guidance on how to tailor screening for older survivors—what role life expectancy, risk of recurrence, patient preferences, or the tradeoffs associated with mammography should play,” Dr. Freedman stated. “The use of mammography for older survivors has been highly inconsistent. With the number of older women who will be diagnosed with breast cancer expected to increase in the coming years, it’s important that we find ways to individualize decisions for each patient’s circumstances and preferences.”
The new guidelines apply to breast cancer survivors who have completed their treatment with surgery, chemotherapy, and radiation therapy but who still may be receiving hormonal therapy. The recommendations vary by age, life expectancy, and breast cancer history and risk considerations. Most hormone receptor–positive and ERBB2-negative tumors as well as stage I ERBB2-positive or triple-negative tumors were considered to be lower-risk cancers; stage II to III triple-negative or ERBB2-positive tumors, as well as some hormone receptor–positive tumors, were considered to be higher-risk cancers.
• Survivors aged 75 to 79: Those with a history of lower-risk cancers and a life expectancy up to 10 years should consider discontinuing surveillance mammography. Those with a history of higher-risk cancer should continue surveillance mammography unless life expectancy is less than 5 years.
• Survivors aged 80 to 84: Those with a history of lower-risk cancers and a life expectancy up to 10 years should consider discontinuing surveillance mammography. Those with a history of higher-risk cancer should consider discontinuing surveillance mammography unless life expectancy is more than 5 years.
• Survivors aged 85 and older or with a life expectancy of less than 5 years: These women should discontinue surveillance mammography unless they are “in extraordinary health or have a strong desire to continue.”
Harms and Limited Benefits
As noted in the consensus statement report: “The primary harms associated with mammography include false-positive results and anxiety associated with diagnostic testing and treatment, some of which may be amplified in breast cancer survivors.”
The panel cited a study that found “in more than 10 years of screening 10,000 women in their 70s, a total of 20 breast cancer deaths will be averted, while 2,000 false-positive results will occur and 130 patients will be overdiagnosed.”2 An updated review of studies from 2014 to the present “did not identify new findings to modify these estimates,” the authors added. The literature review suggested only limited benefits with screening mammography for older women, “likely due,” the authors pointed out, “to the more than 10-year lag required to realize small improvements in breast cancer mortality and the low rates of life-threatening breast cancer events among older women with or without a history of breast cancer.”
Ongoing Clinical Exams
The expert panel that formulated the guidelines also recommended “ongoing clinical breast examinations and diagnostic mammography to evaluate clinical findings and symptoms, with reassurance to patients that these practices will continue.”
“Patients should understand,” Dr. Freedman said, that when physicians recommend discontinuation of surveillance mammography, “it is not that we don’t want to see them anymore. We still want to examine them. We still want to check in on them, but we just don’t know that mammography forever is going to add to their care. Checking in with people, symptom review, physical exam, are always important.”
Estimates of Life Expectancy: More Than Just Age
“Most clinicians felt that estimations of life expectancy, more than age, should inform the timing of the discussion,” the authors wrote. “Although primary and geriatric care clinicians reported comfort discussing life expectancy with patients, oncology clinicians reported discomfort with such discussions.”
“How you frame these patient discussions has a huge impact, and you have to be careful,” Dr. Freedman said. “Some clinicians talk about this very openly, and they know how to do it. For other clinicians, it is much harder. When you are in a curative setting for breast cancer and follow-up, you don’t talk as much about life expectancy beyond breast cancer risks. It is really up to the patient and the clinician how they want to have the conversation.”
As described in the consensus statement, life expectancy calculations are based on the individual’s medical history, degree of functional independence, smoking history, fall history within the past year, and recent hospitalization.
“I sometimes calculate life expectancy ahead of time or just have a sense of it from knowing that patient for a long time, and I don’t have to tell her what her life expectancy is in order to have this conversation. The truth is, if somebody has a limited life expectancy, you can have a very good discussion without even saying that,” Dr. Freedman added. “You can say, ‘Mammograms don’t help people forever. Your other medical conditions may be more pressing, and there are downsides to mammography.’”
Easing Into the Idea
In focus groups, clinicians “supported discussing continuation of mammography for a few years before they might recommend it, so that patients can ‘ease into the idea’; it’s not just a one-time conversation,” the authors reported. “Surveillance mammography every 2 years may be preferred by some women, perhaps easing a transition to [its] discontinuation over time,” they added.
When the subject of discontinuing mammography is first broached, some patients may express resistance. Even knowing the risks and harms of mammography, a patient may “just feel more comfortable” having it, Dr. Freedman said. “It is hard to pull back, and it takes a real conversation to do that. At some point, I try to convince patients to stop. Sometimes, it takes a long time to do that. If you have to ease into it, that is perfectly fine.”
Focusing on Low Risk of In-Breast Recurrence
Framing the discussion around a low risk of breast cancer coming back over life expectancy is one suggested strategy. “Most cancer survivors perceive the cancer risk in their breasts to be pretty high. Because this has happened to them once, they are going to have another breast cancer event,” Dr. Freedman said. “But in many cases, their breast cancer risk is lower than [that in] the general populations because the hormonal therapies prevent new cancers, in addition to preventing their old cancer from coming back.” Hormonal therapies can be so effective that breast cancer survivors “often have a lower chance of developing a breast cancer than women their same age” who never had breast cancer.
“The literature review confirmed the low risk of in-breast cancer events among older breast cancer survivors,” the panel reported, with particularly low rates among patients with hormone receptor–positive tumors treated with endocrine therapy. “As a frame of reference, for women without a personal history of breast cancer, the 5-year risk of developing an invasive cancer for a 75-year-old woman at average risk of breast cancer is 2.2%, closely mirroring our risk estimations for new in-breast cancers among survivors with prior low-risk breast cancers.”
Women at Higher Risk of Distant Recurrence
Women who do not receive systemic therapy for ERBB-2 positive or triple-negative cancers have higher estimated rates of ipsilateral cancer recurrence. Some of these patients “have substantial competing distant recurrence risk that mammograms do not detect,” the authors pointed out.
“If a patient has, for instance, a very large, stage III triple-negative cancer, the risk for her is more pressing for a distant recurrence, metastatic disease, than an ipsilateral cancer,” Dr. Freedman explained. “Her competing risks for that are actually higher.” So, although she may feel more comfortable knowing her mammogram showed no evidence of cancer,” Dr. Freedman said, “the risk is actually not so much in the breast but elsewhere.”
DISCLOSURE: Dr. Freedman has received institutional research funding from Eisai, Genentech/Roche, and Puma Biotechnology.
REFERENCES
2. Walter LC, Schonberg MA: Screening mammography in older women: A review. JAMA 311:1336-1347, 2014.
