What is the recommended treatment for a patient with node-negative, hormone-positive, HER2 (Human Epidermal growth factor Receptor 2)-negative breast cancer?

Treatment for Node-Negative, Hormone-Positive, HER2-Negative Breast Cancer

For patients with node-negative, hormone-positive, HER2-negative breast cancer, endocrine therapy is the cornerstone of treatment, with the addition of adjuvant chemotherapy for selected higher-risk patients based on tumor characteristics and genomic testing. 1, 2

Endocrine Therapy Options

• Tamoxifen 20 mg daily for 5 years is the standard endocrine therapy for premenopausal women with node-negative, hormone-positive breast cancer 3
• For postmenopausal women, aromatase inhibitors (AIs) are recommended as first-line endocrine therapy 1
• Extended endocrine therapy beyond 5 years may be considered for higher-risk patients, particularly those with larger tumors or other adverse features 4

Risk Assessment and Chemotherapy Decisions

• Genomic assays (such as Oncotype DX, MammaPrint) should be used to guide adjuvant chemotherapy decisions for patients with node-negative, hormone-positive, HER2-negative breast cancer 1
• Patients with low genomic risk scores can generally be treated with endocrine therapy alone, avoiding unnecessary chemotherapy toxicity 2, 4
• Patients with high genomic risk scores should receive chemotherapy followed by endocrine therapy to reduce recurrence risk 1

Recommended Chemotherapy Regimens (When Indicated)

For patients who require chemotherapy based on risk assessment:

• Docetaxel-cyclophosphamide (TC) for 4 cycles is recommended as an effective non-anthracycline regimen 1
• Doxorubicin-cyclophosphamide followed by weekly paclitaxel is another standard option 1
• Dose-dense regimens may be considered for higher-risk patients 1

Treatment Algorithm

1. Assess risk factors:

   • Tumor size
   • Grade
   • Lymphovascular invasion
   • Patient age
   • Genomic assay results 2, 4

2. For low-risk disease:

   • Endocrine therapy alone for 5 years 1
   • Premenopausal: Tamoxifen 20 mg daily 3
   • Postmenopausal: Aromatase inhibitor 1

3. For intermediate to high-risk disease:

   • Adjuvant chemotherapy followed by endocrine therapy 1
   • Consider extended endocrine therapy beyond 5 years 4

Special Considerations

• Ovarian suppression with GnRH agonists may be added to tamoxifen for higher-risk premenopausal patients 1
• Male patients with hormone-positive breast cancer should receive tamoxifen with consideration of GnRH analog 1
• Monitoring for endocrine therapy side effects is essential, including bone health assessment for patients on aromatase inhibitors 4

Common Pitfalls to Avoid

• Failing to obtain genomic testing in appropriate candidates, which may lead to over-treatment with chemotherapy in low-risk patients 2
• Discontinuing endocrine therapy prematurely due to side effects rather than managing them appropriately 4
• Not recognizing that adherence to endocrine therapy is crucial for optimal outcomes - regular assessment of compliance is important 4
• Overlooking the importance of bone health monitoring in patients on aromatase inhibitors 1