An international team of researchers has recently announced positive results for EndoPredict, a second-generation prognostic gene expression test for breast cancer recurrence by Myriad Genetics Inc, Salt Lake City.

Results of the team’s study, first published online in the Journal of the National Cancer Institute, demonstrated that EndoPredict (EPclin) was superior to the first-generation Oncotype DX breast cancer recurrence score (RS) for predicting long-term recurrence of ER+, HER2– primary breast cancer.1

“This important study demonstrated that EndoPredict more accurately predicted the recurrence of breast cancer up to 10 years after diagnosis in patients with ER+, HER2– breast cancer than the other test studied,” says Jack Cuzick, PhD, FRS, a study investigator and director of the Wolfson Institute of Preventive Medicine. “These findings will help physicians identify patients who do not need adjuvant chemotherapy following surgery, resulting in a more personalized treatment for their patients.”

The study included 928 women from the translational substudy of the Arimidex, Tamoxifen, alone or in combination (TransATAC) trial, and compared the prognostic power of EndoPredict to that of the first-generation Oncotype DX test. The primary endpoint of the study was distant relapse-free survival. The team’s analysis showed that EndoPredict markedly outperformed Oncotype DX across the 10-year follow-up period, with prognostic power more than four times higher (EPclin: LRX2 = 139.3; RS: LRX2 =29.1).

Using predefined cutoffs, EndoPredict and Oncotype DX identified 58.8% and 61.7% of patients as low-risk, with hazard ratios for low- versus non-low-risk of 5.9 and 2.7, respectively.

The study authors noted that “EPclin’s superior ability to classify patients as low-risk was further demonstrated by the similar number of patients classified as low-risk by RS coupled with a substantially lower 10-year recurrence rate (5.8% for EPclin versus 10.1% for RS).”

“EndoPredict significantly outperformed the first-generation prognostic test in this head-to-head study, especially for late distant recurrences and in node-positive patients,” says Ralf Kronenwett, MD, a study investigator and chief scientific and medical officer at Sividon Diagnostics GmbH, Cologne, Germany. “Additionally, EndoPredict did not classify any patients as intermediate risk, while Oncotype DX classified 28% of [patients] as intermediate risk—which can be confusing for clinicians trying to make treatment decisions.”

For more information, visit Myriad.

REFERENCE

  1. Buus R, Sestak I, Kronenwett R, et al. Comparison of EndoPredict and EPclin with Oncotype DX Recurrence Score for prediction of risk of distant recurrence after endocrine therapy. J Natl Cancer Inst. 2016;108(11):djw149; doi: 10.1093/jnci/djw149.