Dr Diab on Using the BCI for Recurrence Risk Assessment in HR+ Breast Cancer

“We need to identify every [patient]; understand [their] risk, preference, and risk tolerance; and be able to apply the information to make the right decision for that particular woman.”

Sami Diab, MD, medical director of the Center for Cancer and Blood Research at the Pagosa Springs Medical Center, discussed the clinical significance of precision prognostics and individualized risk assessment for premenopausal patients with early-stage, hormone receptor (HR)–positive, node-negative breast cancer.

Diab emphasized the critical role of the Breast Cancer Index (BCI), a genomic assay, in identifying a specific subset of patients with HR-positive breast cancer with a minimal risk of distant recurrence. He noted that by referring to data from the landmark phase 3 SOFT (NCT00066690) and TEXT (NCT00066703) trials, oncologists can now move away from a one-treatment-fits-all approach toward highly individualized therapeutic strategies.

Diab pointed out that the BCI model, specifically using a minimal-risk cutpoint of 3.0, allows for the identification of patients with a less than 5% risk of recurrence over a 10-year period. According to research by Diab and colleagues, patients categorized as having minimal risk across various SOFT and TEXT treatment cohorts demonstrated low rates of distant recurrence–free interval (DRFI) at 10 years. In the SOFT trial, the minimal-risk group of all patients had a 10-year DRFI rate of 2.3% (95% CI, 0.9%-6.0%). When broken down by treatment arm, patients who received tamoxifen alone had a 10-year DRFI rate of 3.5% (95% CI, 0.9%-13.3%), whereas those who received ovarian function suppression combined with either exemestane or tamoxifen had a 10-year DRFI rate of 1.7% (95% CI, 0.4%-6.6%). Similarly, the minimal-risk cohort of patients in the TEXT trial had a 10-year DRFI rate of 2.0% (95% CI, 0.7%-6.2%).

Diab emphasized that having access to such granular, low-risk data adds a vital dimension to the clinical discussions between oncologists and patients. Based on these data, the study investigators reported that for patients identified as being at minimal risk, the perceived benefit of more intensive treatments, such as ovarian function suppression, may be outweighed by the risks and adverse effects associated with the therapies. Consequently, these findings suggest that patients in the minimal-risk category may be appropriate candidates to receive tamoxifen alone, potentially avoiding the added toxicity of ovarian function suppression–containing regimens. Ultimately, Diab stressed the necessity of understanding each patient’s risk profile, personal preferences, and risk tolerance.