Study on Gene Expression and Breast Cancer Death Risk
Author Information
Author(s): Laurel A Habel, Steven Shak, Marlena K Jacobs, Angela Capra, Claire Alexander, Mylan Pho, Joffre Baker, Michael Walker, Drew Watson, James Hackett, Noelle T Blick, Deborah Greenberg, Louis Fehrenbacher, Bryan Langholz, Charles P Quesenberry
Primary Institution: Kaiser Permanente
Hypothesis
The Recurrence Score from the Oncotype DX assay can predict the risk of breast cancer death among lymph node-negative patients.
Conclusion
The Recurrence Score is strongly associated with the risk of breast cancer death among ER-positive patients, regardless of tamoxifen treatment.
Supporting Evidence
- The Recurrence Score was associated with risk of breast cancer death in both tamoxifen-treated and untreated patients.
- Approximately 50% of patients had low risk Recurrence Score values.
- The study included a large population of women diagnosed and treated at multiple hospitals.
Takeaway
This study found that a special test can help doctors know which breast cancer patients are at higher risk of dying from their cancer, even if they didn't have chemotherapy.
Methodology
A case-control study was conducted among 4,964 patients diagnosed with node-negative invasive breast cancer, comparing those who died from breast cancer to matched controls.
Potential Biases
Potential bias due to the retrospective nature of the study and reliance on historical medical records.
Limitations
The study lacked ER status from medical records for many patients, and only about 30% were treated with tamoxifen, limiting analysis.
Participant Demographics
The study included racially and ethnically diverse women diagnosed with lymph node-negative invasive breast cancer, primarily aged 50 and older.
Statistical Information
P-Value
0.003
Confidence Interval
95% CI 1.7–3.9% for low risk, 95% CI 6.3–14.9% for intermediate risk, 95% CI 7.6–22.8% for high risk in tamoxifen-treated patients.
Statistical Significance
p<0.05
Digital Object Identifier (DOI)
Want to read the original?
Access the complete publication on the publisher's website