A review of medical records for almost 200 patients with breast cancer suggests that more selective use of biomarker testing for such patients has the potential to save millions of dollars in health care spending without compromising care. These findings were published in The American Journal of Surgical Pathology (2015; doi:10.1097/PAS.0000000000000424).
Specifically, waiting to perform these tests until a patient has a full excisional biopsy instead of “reflexively” or automatically testing for them on initial small “core” biopsies could save as much as $117 million, according to the study.
Pathologists traditionally have tested for the biomarkers estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) on breast cancers in excisional biopsy specimens, when a surgeon removes all or a large portion of the tumor, to help guide drug treatment.
Over the past 10 years, however, there’s been a shift toward testing of core biopsies, which are the initial small samples of breast cancer removed through a small needle, for these markers, said senior study author Pedram Argani, MD, director of the Breast Pathology Service at The Johns Hopkins Hospital in Baltimore, MD, and a professor of pathology and oncology at the Johns Hopkins University School of Medicine.
“The main reason is that some of these patients may receive chemotherapy before their surgery (neoadjuvant chemotherapy) instead of after (adjuvant chemotherapy), and if they receive neoadjuvant chemotherapy, knowing the markers beforehand is important,” explained Dr. Argani.
To investigate whether smarter, less routine use of small sample marker testing would make sense clinically and financially, researchers led by Christopher J. VandenBussche, MD, PhD, of the Johns Hopkins University School of Medicine, studied records of 197 patients with breast cancer who had so-called reflex biomarker testing done after small sample core needle biopsy. Among those patients, just 27 (13.6%) received chemotherapy before surgery, and eight (4%) showed no residual cancer during excisional biopsy. In those cases, researchers noted, biomarker testing on the core biopsy was necessary.
However, none of the remaining 162 patients received chemotherapy before surgery, and that treatment was considered only in a minority of those patients. Only five patients (3%) were seen by a radiation oncologist and medical oncologist before surgery, while only six (4%) were seen only by a medical oncologist. Forty-four patients (26%) visited only a radiation oncologist before surgery, but these visits were largely for decisions about local therapy, such as lumpectomy versus mastectomy, not chemotherapy.
On repeat testing after excisional biopsy, researchers noted that three of the 18 cancers (17%) that were ER-negative in core biopsy samples were now found to be positive on excision, and one of the 24 (4%) cancers that was PR-negative in core biopsy samples was now positive on the excision. On repeat HER2 testing, one of the 42 cancers (2.4%) that was HER2-negative in the core biopsy was positive on the excision. These results are consistent with those of other research groups, indicating that testing the larger sample helps pick up tumors that carry biomarkers in some areas but not others and that are eligible for targeted therapy, Dr. Argani said.
“We suggest that clinical breast cancer teams consider stopping the practice of reflex testing of core needle biopsies, because the results typically do not guide the next step in therapy,” Dr. Argani said. “A more logical, cost-effective approach would be to perform such testing only if chemotherapy before surgery is a serious consideration for that individual patient.”