The Xpert Breast Cancer Insight Test Predicts Distant Recurrence and Overall Survival in ER-Positive, HER2-Negative...

Area of Science:

• Oncology
• Genomics
• Clinical Validation

Background:

• The Xpert Breast Cancer Insight (BC Insight) test is a novel multigene assay designed for breast cancer prognostication.
• It utilizes three target and three reference genes to assess risk in breast cancer patients.

Purpose of the Study:

• To validate the clinical utility of the BC Insight test.
• To assess the prognostic capability of the BC Insight test for distant recurrence (DR) and overall survival (OS).

Main Methods:

• The BC Insight test was evaluated on 1278 formalin-fixed, paraffin-embedded surgical specimens.
• Specimens were from postmenopausal women with ER-positive, HER2-negative primary breast cancer and 0-3 involved lymph nodes.
• Time to DR and OS were analyzed using Cox models.

Main Results:

• The BC Insight test classified 70.2% of evaluable patients as "low risk".
• The Xpert BC Insight Risk Score (XRS) demonstrated strong prognostic value for DR (HR 1.93) and OS (HR 1.45).
• At 10 years, low-risk patients had significantly better metastasis-free survival (95.3%) and overall survival (89.6%) compared to high-risk patients.

Conclusions:

• The Xpert BC Insight Risk Score (XRS) and Risk Category (XRC) are prognostic for DR in postmenopausal women with ER+/HER2- breast cancer.
• The BC Insight test accurately predicted OS, especially in patients with 1-3 involved lymph nodes.