Delphi Diagnostics

Delphi Diagnostics guides personalized breast cancer therapy decisions with the Endocrine Activity Index

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The EAI test is a gene expression profile (GEP) test that measures transcriptional activity related to Estrogen Receptor (ER) and Progesterone Receptor (PR) in breast cancer tumor tissue to yield an EAI Score1

  • Expression of 18 genes representing ER and PR activity is measured in a tumor sample from core biopsy or surgical resection
  • The ER/PR activity index is further adjusted for baseline prognosis using molecular subtype genes (RNA4 signature) and the clinical factors of tumor size and regional lymph node involvement to yield the Endocrine Activity Index (EAI) score.

The analytical and clinical validity of the EAI technology  has been established through multiple prospective-retrospective studies from randomized clinical trials.1-4

*EAI is known in scientific publications as the Sensitivity to Endocrine Therapy (SET) Test (includes both SETER/PR and SET2,3 Indexes).

These studies have shown that the technology behind the EAI is:

  • A consistent prognostic indicator for long term outcomes (DFS, EFS or DRFS) in Stage II-III breast cancer patients
  • Independent from other prognostic tests: Oncotype DX, Mammaprint and PAM50
  • Predictive for response to dose-intense chemotherapy in the 12-year outcomes analysis of the CALGB 9741 trial4

Based on these studies, EAI currently has two main applications:

  • Prognostic for 5-year disease-free survival in Stage II/III, HER2- HR+ patients on standard-of-care therapy
  • Predictive of survival benefit from dose-intense chemotherapy in Stage II/III, HER2- HR+ patients, independent of menopausal status

References:

  1. Du L, Yau C, et al. Predicted sensitivity to endocrine therapy for stage II-III hormone receptor-positive and HER2-negative (HR+/HER2-) breast cancer before chemo-endocrine therapy. Ann Oncol. 2021;32(5):642-51. Epub 2021/02/23. doi: 10.1016/j.annonc.2021.02.011. PubMed PMID: 33617937
  2. Suman VJ, Du L, Hoskin T, Anurag M, Ma C, Bedrosian I, Hunt KK, Ellis MJ, Symmans WF. Evaluation of Sensitivity to Endocrine Therapy Index (SET2,3) for Response to Neoadjuvant Endocrine Therapy and Longer-Term Breast Cancer Patient Outcomes (Alliance Z1031). Clin Cancer Res. 2022 Aug 2;28(15):3287-3295. doi: 10.1158/1078-0432.CCR-22-0068. PMID: 35653124; PMCID: PMC9357183
  3. Speers CW, Symmans WF, Barlow WE, Trevarton A, The S, Du L, Rae JM, Shak S, Baehner R, Sharma P, Pusztai L, Hortobagyi GN, Hayes DF, Albain KS, Godwin A, Thompson A. Evaluation of the Sensitivity to Endocrine Therapy Index and 21-Gene Breast Recurrence Score in the SWOG S8814 Trial. J Clin Oncol. 2023 Jan 17:JCO2201499. doi: 10.1200/JCO.22.01499. PMID: 36649570
  4. Metzger, Otto et al. Measurement of endocrine activity (SET2,3) related to prognosis and prediction of benefit from dose-dense (DD) chemotherapy in estrogen receptor-positive (ER+) cancer: CALGB 9741 (Alliance). 2022 American Society of Clinical Oncology Annual Meeting, Chicago, IL. June 3-7, 2022. https://meetings.asco.org/abstracts-presentations/208274  and 2023 San Antonio Breast Cancer Symposium, invited presentation.