Most women in the early stages of breast cancer will be subjected to advanced imaging tests when modern medical guidelines say there’s only a sliver of a chance they may uncover anything.

That’s the conclusion of a new study, which was published Monday in the Canadian Medical Association Journal.

Researchers said they found that about 86 percent of women with early-stage breast cancer will undergo, on average, 3.7 imaging tests before and after surgery to detect whether their cancer has spread.

The study examined 26,547 women in the Ontario area of Canada who were diagnosed with stage 1 or stage 2 breast cancer between 2007 and 2012. Of those women, 80 percent with stage 1 and 93 percent with stage 2 received advanced imaging tests.

“Despite guidelines against imaging to detect radiologically evident distant metastases, our results show that this practice is very common among patients with early-stage breast cancer in Ontario,” Dr. Mark Clemons, an oncologist at the Ottawa Hospital and the University of Ottawa, said in a statement.

It should be noted this study addresses tests for spreading cancer in diagnosed breast cancer treatments, not regular mammograms recommended by the American Cancer Society and other organizations.

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More Tests Cause Undue Stress

Because the likelihood of cancer metastasis during these stages is low — 0.2 percent in stage 1 and 1.2 percent in stage 2 — the American Society of Clinical Oncology, Cancer Care Ontario, and the National Comprehensive Cancer Network don’t recommend imaging tests to search for spreading cancer cells in asymptomatic women.

These imaging tests, including CT, MRI, and PET scans, to investigate possible metastases has increased. They now comprise 41 percent of all initial tests in early-stage breast cancer.

The study authors said surgeons and oncologists ordered the most tests. Surgeons ordered 74 percent of preoperative tests and oncologists ordered 41 percent of postoperative tests.

Drs. Daniel Rayson and Geoff Porter of Queen Elizabeth II Health Sciences Centre and Dalhousie University in Halifax, Nova Scotia, say these surgical and oncological teams may have laudable goals to reassure and support anxious, newly diagnosed patients.

“Patients are often blindsided by a cancer diagnosis and rely on their medical team to be as certain as possible that their disease can be cured and they are not dying,” they wrote in commentary accompanying the study.

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The Risk of False-Positive Results

Researchers say the chance of false-positive results are high, potentially leading to more invasive tests, treatment delays, and undue mental stress.

The National Guideline Clearinghouse, part of the U.S. government’s Agency for Healthcare Research and Quality, says while doctors encourage these tests, they often neglect to educate patients about radiation exposure, the dangers of chasing false-positives, and the anxiety related to these tests.

“Ordering advanced imaging studies may provide patients with short-term reassurance but seldom allays long-term fears of recurrence that are ubiquitous in cancer survivors,” their website states.

Besides heightening the anxiety of undergoing the tests and awaiting their results, the false-positives can have a cascading effect of even more tests and unnecessary treatments, all which increase costs and use of healthcare resources.

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The Importance of Patient Input

The Ontario researchers note there were variations in imaging test usage between geographic regions and between community hospitals and academic institutions. They note for the guidelines to be universally followed, more than just publicizing guidelines is needed.

“These strategies will also require patient engagement,” the authors conclude.

Even while some patients may want every possible test to be done to ensure their health and safety, the researchers say doctors must be the “knowledge brokers” of evidence-based guidance for their patients.

“To do so effectively takes time, energy and good interdisciplinary communication,” the commentary authors wrote. “For most patients with newly diagnosed stage I and II breast cancer, reflexively ordering staging investigations does not help relieve stress, nor does it detect disease.”