MARLBOROUGH, Mass. — Hologic Inc. and its subsidiary Biotheranostics Inc. will present new data at the 2026 ASCO Annual Meeting showing how Breast Cancer Index Test results influence extended endocrine therapy decisions for patients with early-stage, hormone receptor-positive breast cancer.
The company said the latest analysis found that physician recommendations for extended endocrine therapy increased by more than 30% among patients identified by the Breast Cancer Index Test as likely to benefit. Recommendations decreased by nearly 40% for patients identified as unlikely to benefit.
The findings will be presented June 1 at the ASCO meeting. The data come from a new analysis of the ongoing BCI Registry Study, which evaluates how physicians use prognostic and predictive Breast Cancer Index Test results in real-world treatment decisions.
The Breast Cancer Index Test is used to help guide extended endocrine therapy decisions beyond five years. Hologic said the test has guideline recognition from the National Comprehensive Cancer Network and the American Society of Clinical Oncology for that purpose.
“Understanding who is likely to benefit from extended endocrine therapy is critical to personalizing care,” said Sami Diab, M.D., Medical Director, Oncology at Hologic. “Findings from the BCI Registry Study continue to highlight the real-world impact of the Breast Cancer Index Test in helping physicians make more informed treatment recommendations for their patients.”
In the overall study population, the percentage of patients recommended for extended endocrine therapy fell from 54.6% before Breast Cancer Index testing to 41.2% after testing. The percentage of patients not recommended for extended endocrine therapy increased from 44.9% before testing to 58% after testing.
Among patients identified by the test as likely to benefit from extended endocrine therapy, physician recommendations for treatment increased from 60.4% before testing to 90.6% after testing.
Among patients identified as unlikely to benefit, recommendations decreased from 51.1% before testing to 11.8% after testing.
“Decisions about extended endocrine therapy are complex, requiring physicians to balance recurrence risk, potential side effects, and clinical and pathologic factors,” said Tara B. Sanft, M.D., of Hartford Healthcare and lead author of the study. “Findings from the BCI Registry Study suggest that relying on those factors alone may not provide enough information for physicians and patients to make decisions with confidence. Genomic testing with the Breast Cancer Index Test provides additional insight into tumor biology, helping physicians refine extended endocrine therapy recommendations and better identify which patients are most likely to benefit.”
