Myriad Genetics presented new data on its EndoPredict test, saying it can accurately forecast which women with newly diagnosed ER-positive, HER2-negative breast cancer will see the most benefits from adjunctive chemotherapy.
The company also said the test can predict those who will be unlikely to see benefits from extended endocrine treatments over a five-year period and can forgo therapy, as well as offer a long-term prognosis on the risk of disease recurrence. The studies were presented at the San Antonio Breast Cancer Symposium.
A retrospective analysis of five prospective studies evaluated 3,746 women with breast cancer that received five years of endocrine therapy either alone or in combination with chemotherapy. The analysis’ primary goal was to establish 10-year rates of distant recurrences.
Patients with a high EndoPredict score that also received chemotherapy had significantly lower 10-year risks than those who received endocrine treatment alone. There were no significant differences between patients who received low EndoPredict scores, according to Myriad.
A second analysis gauged the test’s ability to predict distant breast cancer recurrence up to 15 years. It included 1,702 patients who received five years of endocrine therapy alone, 62.2% of which had low EndoPredict scores.
The results showed the test was able to predict early and late distant recurrence regardless of nodal status, with women with low EndoPredict scores having reduced risks compared to those with high scores.
“In this study, women with a high EndoPredict score were four times more likely to experience a breast cancer recurrence setback,” said principal investigator Martin Filipits, Ph.D., of the Institute of Cancer Research at the Medical University of Vienna, Austria.
“Importantly, the low-risk group had a 4% rate of distant recurrence in years 5-15 compared to 16% in the high-risk group, which suggests that EndoPredict can help select patients who can safely forgo extended endocrine therapy beyond five years,” Filipits said in a statement.