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Press Room

June 5, 2017

New Data Affirms Value of Breast Cancer Index (BCI) in Identification of Early Stage ER+ Breast Cancer Patients Appropriate for Extended Endocrine Therapy (EET)


• Largest Study of BCI Patient Cases Confirms Importance of BCI Across Patient Spectrum
• Studies presented at 53rd Annual Meeting of the American Society of Clinical Oncology


SAN DIEGO, Calif., June 5, 2017 – Biotheranostics, Inc. today announced new data further demonstrating the importance of BCI in clinical practice. In a study of more than 14,000 cases, the largest patient study for BCI, BCI identified 31.5% of patients with node-negative (LN-) breast cancer – those who are typically considered at lower risk for recurrence and who may not be recommended for extended endocrine therapy (EET) – as high risk of recurrence and high likelihood of benefit from an additional 5 years of therapy. Conversely, the study also identified 16% of node positive (LN+) patients who are typically considered at higher risk of recurrence and likely to be recommended extended therapy as low risk of recurrence between years 5-10 and low likelihood of benefit from extended endocrine therapy. A separate study of the BCI database stratified patients by age, and demonstrated that in patients aged 75 or older, for whom treatment considerations are often more complex, BCI identified similar rates of patients with HR+, LN–breast cancer as having high vs. low risk of late distant recurrence and high vs. low likelihood of benefit from EET.

The studies are being presented at the 53rd Annual Meeting of the American Society of Clinical Oncology (ASCO) being held in Chicago this week.

“These clinical experience studies further underscore that BCI is an important tool to help physicians to better personalize EET recommendations -- informing patient selection for extended therapy, while potentially minimizing exposure to unnecessary side effects and toxicities for the patients who are at low risk of late distant recurrence and low likelihood of benefit from EET,” said Catherine Schnabel, PhD, Chief Scientific Officer, Biotheranostics.

In the largest BCI patient study to date (n=14,463), researchers evaluated data from the BCI Clinical Database for Correlative Studies – a de-identified database that contains more than 50 data points including tumor size, grade, LN status, and BCI results. The analysis was specifically designed to better understand how physicians are using BCI in the clinic, and to affirm its use across the patient spectrum. Of the patient cases evaluated, the median age was 58.2 years. 47 cases were Stage I, and the majority of cases had Grade 1 (29%) or Grade 2 (51%) tumors. Like previously presented BCI data, the study demonstrated that more than 30% of node negative patients were classified as high risk of late distant recurrence.

In consideration of the complexities of treating older patients, a second study compared cases of older patients (≥75y) vs. younger patients. Consistent with previous studies of BCI, BCI identified 31.9% of these patients who would typically be considered low risk and not prescribed extended endocrine therapy, as high risk of late distant recurrence and high likelihood of benefit from EET.

"What’s important about these findings is that for older patients, the stakes are often considerably higher because of potential comorbidities (e.g., bone loss), shorter life expectancies, quality of life (QoL) concerns, and overall life expectancy etc., said Dr. Schnabel. “BCI identified patients likely to benefit from EET, but perhaps most importantly for this age group, those for whom EET would be unlikely to show benefit. This additional information can be very helpful to clinicians in treatment planning for older patients."

Additional Studies

Other new data supporting the clinical utility can be found published in the Journal of Clinical Oncology in conjunction with the annual meeting. Those abstracts include:

  • Likelihood of late relapse assessed by the Breast Cancer Index (BCI) in LN-invasive lobular compared to invasive ductal carcinoma (abstract #: e12025)
  • Correlation of Breast Cancer Index (BCI) prognostic and predictive results to Ki67 and tumor grade in early stage HR+ breast cancer.(abstract #: e12075)

About Breast Cancer IndexSM

BCI is a molecular, gene expression-based test uniquely positioned to help identify patients best suited for extended endocrine treatment. It is the only validated, commercially available test with data demonstrating prognostic risk of recurrence out to 15 years, as well as prediction of likelihood of benefit from extended endocrine therapy (treatment in years 5-10). The breakthrough test helps oncologists and patients navigate the difficult trade-off between wanting to take steps to prevent recurrence of their disease and facing significant side effects and safety challenges related to extended endocrine therapy. For more information, visit

About Biotheranostics

Biotheranostics, Inc., is a leader in helping physicians improve the care of cancer patients, offering a suite of proprietary genomics-based molecular diagnostics that allow treatment to be tailored to individual patients. The company's Breast Cancer IndexSM and CancerTYPE ID® tests address a variety of unmet medical needs in the management of cancer patients, and extensive clinical studies have confirmed the accuracy, clinical validity, clinical utility, and cost-effectiveness of the tests. Biotheranostics operates a CLIA-certified, CAP-accredited diagnostic laboratory in San Diego. Learn more at