"What length of treatment is right for me?"

Women diagnosed with early-stage, hormone receptor-positive (HR+) breast cancer are typically treated with anti-estrogen therapy for at least 5 years to reduce the risk of a metastatic recurrence.1 And while some may benefit from continuing treatment, not all do.2-7 Only the Breast Cancer Index® (BCI™) Test is guideline-recognized to tell you whether an additional 5 years (10 total years) of anti-estrogen therapy is likely to benefit you.8,9

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What length of treatment is right for me
"How much
longer until 

I feel like 
myself again?"

The BCI Test Helps You Weigh the Side Effects vs. Benefit of Longer Anti-Estrogen Therapy

If you experience uncomfortable and frustrating side effects as a result of taking anti-estrogen therapy routinely, you are not alone. Many of these may have a negative impact on everyday life and some have the potential to pose an even greater risk to your health.2,5,10

Possible side effects for aromatase inhibitors:11,12


  • Hot flashes
  • Joint pain and stiffness
  • Vaginal dryness
  • Hair thinning
  • High cholesterol
  • High blood pressure
  • Osteoporosis
  • Bone fractures

Possible side effects for tamoxifen:13


  • Mood swings
  • Hot flashes
  • Vaginal dryness
  • Weight gain
  • Early-onset menopause
  • Cataracts
  • Blood clots
  • Endometrial cancer
  • Stroke

RESULTS THAT MAKE A DIFFERENCE

“I knew the [Breast Cancer Index] test was giving me an answer that was specific to my situation rather than just sticking with the standard protocols.” 
—Ashliann, Breast Cancer Survivor & BCI Patient
Ashliann, Breast Cancer Survivor & BCI Test Patient

Your Breast Cancer Timeline

If you’ve been diagnosed with breast cancer, it may be hard to think beyond the minute you’re in. But the results of your BCI Test can help give you and your oncology care team more certainty as you develop your treatment plan.

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mobile bci timeline

Use this conversation guide to ask your doctor if the BCI Test is right for you.

1. Burstein HJ, et al. J Clin Oncol. 2014;32(21):2255-2269. 2. Davies C, et al. Lancet Oncol. 2013;381:805-816. 3. Gray R, et al. J Clin Cancer Inst. 2013;31:(suppl;abstr 5). 4. Jakesz R, et al. J Natl Cancer Inst. 2007;19;99(24):1845-1853. 5. Goss PE, et al. N Engl J Med. 2003;349(19):1793-1802. 6. Mamounas EP, et al. Clin Cancer Res. 2024;30(9):1984-1991. 7. Goss PE, et al. J Natl Cancer Inst. 2005 Sep 7;97(17):1262-71. 8. Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Breast Cancer V.5.2025. © National Comprehensive Cancer Network, Inc. 2025. All rights reserved. Accessed October 28, 2025. To view the most recent and complete version of the guideline, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use or application and disclaims any responsibility for their application or use in any way. 9. Andre F, et al. J Clin Oncol. 2022;40(16):1816-1837. Referenced with permission from the American Society of Clinical Oncology (ASCO®) Clinical Practice Guideline Biomarkers for Adjuvant Endocrine and Chemotherapy in Early-Stage Breast Cancer. © American Society of Clinical Oncology. 2025. All rights reserved. To view the most recent and complete version of the guideline, go online to https://ascopubs.org/jco/special/guidelines [ascopubs.org]. ASCO makes no warranties of any kind whatsoever regarding their content, use of application and disclaims any responsibility for their application or use in any way. 10. Side Effects of Hormonal Therapy for Breast Cancer. BreastCancer.org. Accessed October 28, 2025. https://www.breastcancer.org/treatment/hormonal-therapy/side-effects. 11. Arimidex Full Prescribing Information And Side Effects. Accessed October 28, 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/020541s036lbl.pdf. 12. Aromasin Full Prescribing Information And Side Effects. Accessed October 28, 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/ 2024/020753s025lbl.pdf. 13. Tamoxifen Full Prescribing Information And Side Effects. Accessed October 28, 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2019/021807s006lbl.pdf.