A prospective study has demonstrated that EndoPredict, a 12-gene molecular prognostic test for patients diagnosed with breast cancer, from Myriad Genetics, Salt Lake City, predicts which patients with ER-positive, HER2-negative early-stage breast cancer will benefit from neoadjuvant therapy.1
“This study demonstrated that the EndoPredict test predicted response to neoadjuvant chemotherapy or neoadjuvant endocrine therapy in women with ER-positive, HER2-negative early-stage breast cancer,” says lead author Peter Dubsky, MD, of the Austrian breast and colorectal cancer study group (ABCSG). “Based on these findings and prior studies, we are confident the EndoPredict test can add valuable information to aid in personalized treatment selection in neoadjuvant therapy and provides an important basis for future design of neoadjuvant clinical trials.”

The primary objective of the prospective study was to assess the value of the EndoPredict test for predicting tumor response after neoadjuvant chemotherapy (NaCT) or neoadjuvant endocrine therapy (NET) within the ABCSG-34 trial. The analysis included data from 217 women with HR+ breast cancer. Of these, 134 patients were assigned to receive NaCT (eight cycles of anthracycline/taxane) as recommended by the aggressive clinicopathologic features of their tumors. The remaining 83 patients were clinically identified as having luminal A-like types of breast cancer and were assigned to receive NET (6 months of letrozole). The primary endpoint was residual cancer burden RCB0/I (ie, good tumor response) versus RCB II/III (ie, poor tumor response) at the time of surgery.

In the neoadjuvant chemotherapy group, 125 patients had high EndoPredict scores and nine had low EndoPredict scores. The test results showed that 26.4% of those with a high score showed a good tumor response (RCB0/I) to neoadjuvant chemotherapy, while all patients with a low score showed a poor tumor response. In the ‘luminal A’ group receiving neoendocrine therapy, 39 patients had a high EndoPredict score and 44 had a low EndoPredict score. The results showed that 27.3% of those with a low EndoPredict score and 7.7% with a high score achieved excellent tumor response (RCB0/I) to neoendocrine therapy.

“In this prospective study, we demonstrated that the EndoPredict test is a useful tool preoperatively,” says Ralf Kronenwett, MD, director of international medical affairs at Myriad. “In two distinct ER-positive, HER2-negative cohorts selected by clinicians to receive neoadjuvant chemotherapy or neoadjuvant endocrine therapy, EndoPredict identified patients with poor neoadjuvant treatment response. Clinicians can use information to determine who might forgo these therapies prior to surgery.”

For more information, visit Myriad Genetics.


1. Dubsky PC, Singer CF, Egle D, et al. “The EndoPredict score predicts response to neoadjuvant chemotherapy and neoendocrine therapy in hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer patients from the ABCSG-34 trial.” Eur J Cancer. 2020;134:99–106; doi: 10.1016/j.ejca.2020.04.020.