Hologic’s Breast Cancer Index Test Alters Treatment Plans for 42% of Patients — Hologic, Inc.

Event summary

Hologic’s Breast Cancer Index (BCI) test led to changes in extended endocrine therapy recommendations for 42% of patients, per a study published in JAMA Network Open.
The study involved nearly 3,000 patients with early-stage, hormone receptor-positive (HR+) breast cancer across multiple institutions.
Two-thirds of the changes involved physicians recommending against extending treatment, highlighting the test’s role in personalized care.
Hologic introduced an updated BCI report option in July 2026, providing earlier insights at the time of diagnosis.

The big picture

Hologic’s data underscores the growing role of genomic testing in tailoring breast cancer treatment, addressing both recurrence risk and patient quality of life. The findings come as extended endocrine therapy remains a critical but challenging phase of care, with high discontinuation rates due to side effects. The updated BCI report option positions Hologic to capture earlier decision-making moments, potentially expanding its market reach in personalized oncology.

What we're watching

Adoption Dynamics: How the updated BCI report option will affect physician and patient decision-making at the time of diagnosis.
Competitive Positioning: Whether Hologic can sustain its leadership in personalized oncology diagnostics amid growing competition.
Regulatory Influence: The pace at which guideline recognition from NCCN and ASCO will drive broader clinical adoption of the BCI test.