PHOENIX – Despite clear guidance on lack of benefit and potential harms, many patients with early-stage breast cancers at low metastasis risk have undergone imaging tests for staging, recent retrospective studies have shown.
Nearly one-third of early-stage breast cancer patients received the unnecessary and potentially harmful interventions in one of the two studies presented at a symposium on quality care sponsored by the American Society of Clinical Oncology (ASCO).
Low-risk patients in that study were more likely to undergo imaging if they were younger or had triple-negative disease, among other factors, said researcher Brett Barlow, of the University of Alabama at Birmingham.
Physicians should be further educated about the low-risk nature of early-stage breast cancer, even in subgroups that are perceived to be higher risk, Mr. Barlow said in an interview.
“I think we can reassure physicians that these patients will do well and that these guidelines are based on good data,” he said “There could potentially be an element of distrust in these guidelines in these higher-risk patients, and that may be what’s driving some of these extra tests.”
According to Mr. Barlow, imaging low-risk patients is inconsistent with guidance from Choosing Wisely, an initiative designed to promote discussions between clinicians and patients about medical tests or procedures that are unnecessary.
As part of that initiative, ASCO recommended that PET, CT, and radionuclide bone scans should not be performed for staging of early-stage breast cancer at low risk for metastasis.
There is a lack of evidence that demonstrates a benefit for those imaging modalities in patients with newly identified ductal carcinoma in situ (DCIS) or clinical stage I or II disease, the society said at the time.
Unnecessary imaging can result in unnecessary invasive procedures, overtreatment, radiation exposure, and misdiagnosis, the society said in the guidance, which was published in 2012.
Despite the guidance, 262 out of 872 patients with stage 0-II breast cancer (30%) seen during 2013-2015 underwent imaging, according to results of the single-center retrospective cohort study Mr. Barlow and his coauthors described in a poster presentation.
The median age of the patients who underwent unnecessary imaging was 55 years versus 60 years for patients who did not, according to the researchers.
Risk of inappropriate imaging was increased in younger patients, those with triple-negative disease versus those with any hormone receptor–positive disease, those with higher-stage breast cancer, and those without Medicare insurance, investigators found.
Although it’s unclear whether there were any formal, institution-level efforts to promote the ASCO recommendations during the 2013-2015 period, it was “definitely a topic of debate at the time,” Mr. Barlow said.
“Something we hope to evaluate further is whether we have improved,” he said. “It’s important to set a baseline and see how we did in this area. We look forward to reevaluating that in a few years to see.”
In a separate study, investigators reviewed records from Mount Sinai Health System in New York and found that unnecessary scans were performed in 19% of patients diagnosed with stage I-II breast cancer during 2014-2015.
No cases of metastatic disease were found in 733 patients included in the study, and 43% had false-positive findings, according to Ana I. Velazquez Manana, MD, MS, of Mount Sinai Beth Israel Foundation, New York, and her coinvestigators.
Imaging increased costs by $4,480 per patient, according to the investigators, who found in multivariate analysis that the unnecessary scans were associated with young age, presence of T2 tumor, positive lymph nodes, and triple-negative disease.
“Further educational efforts are needed to avoid unnecessary scans in patients with early-stage breast cancer,” the researchers wrote in an abstract describing the results.
Mr. Barlow reported no disclosures, while one coauthor reported disclosures related to Carevive Systems, Genentech/Roche, Medscape, Pack Health, and Pfizer. Dr. Velazquez Manana and her coauthors had no relationships to disclose, and their study was funded by the Medical Student Rotation for Underrepresented Populations.
SOURCE: Barlow B et al. Quality Care Symposium, Abstract 51. Velazquez Manana AI et al. Quality Care Symposium, Abstract 52.