Researchers wanted to see if they could better identify which younger women with a common, early form of breast cancer have a very low risk of the disease spreading to other parts of the body. They studied over 2,000 premenopausal women with hormone-receptor-positive, node-negative breast cancer who were part of two large clinical trials. The women had received standard hormone-blocking therapy.
The team tested an adjusted version of a tool called the Breast Cancer Index (BCI). This tool looks at tumor biology. The adjusted model reclassified about 18-20% of the women into a new 'minimal-risk' group. For these women, the estimated risk of the cancer spreading within 10 years was low, around 2-2.3%.
No safety issues with the tool itself were reported, as it is a test performed on tumor tissue. The main reason for caution is that this is a research analysis of existing trial data. The tool is not yet ready for routine use to guide treatment. The findings suggest this refined model may one day help doctors and patients have more personalized discussions about long-term risk, but more validation is needed.
