Two prospective real-world studies presented at SABCS show EndoPredict accurately guides decisions on chemotherapy in ER+, HER2- breast cancer

12^th December 2022 During the San Antonio Breast Cancer Symposium (SABCS) on 6-10 December 2022, new prospective long-term and real-world outcome data were presented from two studies on the EndoPredict Breast Cancer Prognostic Test, a gene expression test for ER+, HER2- early-stage breast cancer.

Real-world results from the prospective Charité registry

The first poster presented was titled ‘Retrospective evaluation of outcomes in a real-world, prospective cohort using EndoPredict: Results from the Charité registry’.¹ The real-world results confirm previous clinical studies demonstrating that patients with an EPclin low-risk score can safely forego chemotherapy.

Presented by Prof. Carsten Denkert, Director Institute of Pathology, University Hospital Marburg, Germany, this study surveyed 842 ER+, HER2- (N0-3) women with early breast cancer between 2011 and 2016 who received EndoPredict testing before systemic treatment decision-making.

The study showed that EndoPredict was a significant predictor of recurrence in the absence of chemotherapy (hazard ratio = 4.34, p = 0.0024). The 392 patients with an EPclin low-risk score who were treated accordingly with endocrine therapy alone had a low 5-year risk of distant recurrence (1.6%). This was independent of nodal status, with an exploratory subgroup analysis revealing a 2.4% 5-year risk of distant recurrence in node positive patients.

“These important new EndoPredict data from a prospective registry confirm again our validation data in a real-world setting” said Dr. Ralf Kronenwett, director of International Medical Affairs, Myriad Genetics. “EndoPredict identifies true low-risk patients with node negative or node positive breast cancer who could safely forgo chemotherapy.”

Long-term data from EndoPredict’s first prospective outcome study

The second poster was titled ‘Long-term outcome data using EndoPredict as risk stratification and chemotherapy decision biomarker in hormone receptor positive, HER2-negative early breast cancer’.² Previously published in the Archives of Gynecology and Obstetrics 2020³, the new results provide a longer follow-up and the first long-term prospective outcome data for patients whose systemic therapy recommendation was based on the EndoPredict test result.

Presented by Dr. Evelyn Klein, Department of Obstetrics and Gynecology, Klinikum rechts der Isar, Technische Universität München, Germany, this study collected patient outcome data from 368 women with ER+, HER2- (N0-3) early breast cancer who were enrolled between 2012 and 2015. The new long-term results are based on a median follow-up of 8.2 years.

In this real-world patient group, 5-year distant metastasis free survival (DMFS) was 96.6% for EPclin low-risk patients versus 85.5% for EPclin high-risk patients (hazard ratio = 2.21, p = 0.005). This was consistent regardless of menopausal status, with 63% of premenopausal patients classified as EPclin low-risk.

A benefit was also shown for EPclin high-risk patients who received the recommended chemotherapy compared to those who did not, with a 64% relative reduction in recurrence risk of patients who had been treated with chemotherapy, confirming that EndoPredict can help guide chemotherapy decision-making.

Finally, EndoPredict was shown to have better classification accuracy in comparison to Ki67 subtypes, resulting in a more precise estimation of prognosis. 33.3% of all tumor samples classified as luminal B (Ki67 high) were reclassified as EPclin low-risk, allowing those patients to safely avoid chemotherapy.

EPclin-based risk stratification was significantly associated with improved disease free survival of EPclin low-risk patients compared to EPclin high-risk patients in both Ki67 subtypes (Ki67 low: hazard ratio = 4.0, p = 0.021; Ki67 high: hazard ratio = 3.77, p = 0.022).

Learn more about EndoPredict.

About the studies

The ‘Retrospective evaluation of outcomes in a real-world, prospective cohort using EndoPredict: Results from the Charité registry’ study surveyed patients enrolled in the Charité University Hospital registry who had ER+, HER2- early-stage breast cancer with 0-3 positive lymph nodes. All patients were tested with EndoPredict between 2011 and 2016 before treatment decision-making.

Treatment and recurrence history was obtained from patient surveys, while demographics, clinical characteristics and EndoPredict results were retrieved from patient records. Recurrence estimates were calculated by Cox proportional hazards models and Kaplan-Meier estimates.

The ‘Long-term outcome data using EndoPredict as risk stratification and chemotherapy decision biomarker in hormone receptor positive, HER2-negative early breast cancer’ study reported on 8 years’ follow-up data from the prospective registry study at Technische Universität Munich. This study enrolled 368 women with ER+, HER2- early-stage breast cancer with 0-3 positive lymph nodes whose treatment recommendation was based on the EndoPredict test result.

Demographic, clinical and pathological data, as well as EPclin Risk Class, were assessed for each patient at baseline and therapy recommendations were given during an interdisciplinary tumor board. Patients were evaluated for treatment compliance, local recurrence, distant metastases and survival. Disease-free survival (DFS) was defined as any recurrence or death, while distant metastasis free survival (DMFS) was defined as survival without any distant recurrence.

About Myriad Genetics

Myriad Genetics is a leading genetic testing and precision medicine company dedicated to advancing health and well-being for all. Myriad develops and offers genetic tests that help assess the risk of developing disease or disease progression and guide treatment decisions across medical specialties where genetic insights can significantly improve patient care and lower healthcare costs. Fast Company named Myriad among the World’s Most Innovative Companies for 2022. For more information, visit www.myriadgenetics.eu.  

References

1. Schmitt, Wolfgang et al. “Retrospective evaluation of outcomes in a real-world, prospective cohort using EndoPredict: Results from the Charité registry.” SABCS 2022
2. Klein, Evelyn et al. “Long-term outcome data using EndoPredict as risk stratification and chemotherapy decision biomarker in hormone receptor positive, HER2-negative early breast cancer.” SABCS 2022
3. Ettl, Johannes. et al. “First prospective outcome data for the second-generation multigene test EndoPredict in ER-positive/HER2-negative breast cancer.” Archives of Gynecology and Obstetrics, vol. 302, issue 6, 2020, pp.1461–1467