麻豆传媒

Inappropriate use of staging imaging for patients with early-stage breast cancer decreased after ASCO advised against it in the society's contributions to the American Board of Internal Medicine Foundation's recommendations. The reduction was modest, however, and required reinforcement, said authors of a study in the that examined the issue.

Issam Makhoul, MD, of the CARTI Cancer Center in Little Rock, Arkansas, and colleagues examined data from the linked Medicare-Surveillance, Epidemiology, and End Results (SEER) database. The team assessed how prevalent the inappropriate practice was before the recommendation (2010-2012), immediately after the release (2012-2013), and during a post-release reinforcement period (2013-2015).

Imaging rates fell by only 1.9% in 2013 (P= 0.18) shortly after the guideline was published. However, the rates fell by 12.8% in 2014 (P<0.001) and by 15.8% in 2015 (P<0.01), after the guidelines were reinforced, Makhoul and colleagues reported.

"Our findings, combined with findings from other previous studies, suggest that reinforcement and more frequent, intentional dissemination of high-quality, evidence-based measures are required to induce a more robust change in medical practice and decrease the prevalence of imaging overuse," the authors concluded.

In the following interview, Makhoul, medical director of Clinical Research and an ASCO expert spokesperson, discussed the issue and the study in more detail.

Choosing Wisely recommends against the use of PET, CT, and radionuclide bone scans for the staging of early-stage breast cancer at low risk for metastasis. What evidence shows that these imaging techniques are of little diagnostic benefit for these patients?

Makhoul: In 2011, the American Board of Internal Medicine Foundation launched "Choosing Wisely: The Five Things Physicians and Patients Should Question," an effort to reduce the use of procedures that do not offer a proven benefit, can be harmful, and are costly to patients and the healthcare system. In response to this call to action, ASCO tasked its Cost of Care Task Force committee to find five procedures that are "commonly ordered, expensive, and of unproven clinical benefit."

After extensive review of the literature, we found many retrospective studies and some prospective studies of the utility of these imaging modalities in early breast cancer with no symptoms to suggest metastatic disease.

Early breast cancer is defined as non-invasive breast cancer (DCIS -- ductal carcinoma in situ), stage I, II and III. When PET, CT scan, bone scan, chest x-ray, or liver ultrasound were used in the staging of these patients, the detection rate of occult metastases (that are not associated with symptoms) was low, and most of these metastases were in stage III patients. The risk of occult metastases in patients with DCIS, stage I and II might be 1% or less.

Hence, the recommendation to forgo these tests in DCIS, stage I and II breast cancer in the absence of symptoms to suggest metastases. Imaging studies are considered reasonable for stage III breast cancer patients due to the implications on their management.

What are the potential harms of using these imaging techniques in these patients?

Makhoul: The most important risks to the patients are (1) the risk of false positives -- i.e., benign findings that may look like metastasis -- that are way more common than true positives and may lead to invasive procedures, which may result in harm to the patients; and (2) the patients' anxiety and psychological distress while waiting for the results of the scans or biopsies, which affects quality of life and psychological well-being.

Misuse of limited resources is an important harm to the healthcare system at the time of limited resources to care for underserved patients in dire need of care.

How did you reinforce this recommendation after it was published, and why is reinforcement important to reducing inappropriate practice?

Makhoul: Reinforcement was done by re-publication of the guidelines in medical journals. The golden rule for publication is to publish an article once in one journal. However, for guidelines destined to change patients' and physicians' behavior, re-publication was key to reaching larger audiences and serve as a reminder for those who have had a first exposure to the information.

This strategy worked. We expect repeated reinforcement to decrease use of these procedures even further.

The near 16% reduction in 2015 was significant, but it seems modest. Do you think further reductions closer to 50% or even 100% are possible?

Makhoul: I agree that a 16% reduction is modest, but when we look at a large population (hundreds of thousands) this decrease is significant. In the United States in 2022, new invasive breast cancer will be diagnosed in an estimated 287,850 women and 2,710 men. Sixty-five percent of women with invasive breast cancer are diagnosed with stage I or II (187,102 cases of early-stage breast cancer). Their 5-year survival rate is 99%. An additional 51,400 cases of DCIS will be diagnosed in women.

I think that further reductions of up to 50% or 60% are possible with more reinforcement. I do not think we will be able to achieve a 100% reduction.

Do you plan to follow this trend further to see if rates continue to fall?

Makhoul: We plan to continue the follow-up until the year 2021. This will give us a better understanding of the dynamic of physicians' behavioral change and help us assess the need for more reinforcement.

Read the study here and expert commentary about it here.