Treatment Recommendations for Invasive Ductal Carcinoma

Introduction to Treatment

• The American Society of Clinical Oncology recommends breast-conserving surgery with radiation therapy followed by adjuvant endocrine therapy, with consideration of chemotherapy based on genomic testing results due to the high Ki-67 index for a 1.2 cm, grade 3, ER/PR-positive, HER2-negative invasive ductal carcinoma with Ki-67 40% 1, 2

Surgical Management

• The National Comprehensive Cancer Network recommends breast-conserving surgery with radiation therapy as the preferred approach for T1 tumors, offering equivalent survival outcomes to mastectomy while preserving breast tissue 2
• The American College of Surgeons recommends sentinel lymph node biopsy for axillary staging in clinically node-negative disease 2

Radiation Therapy

• The American Society for Radiation Oncology recommends whole breast radiation therapy following breast-conserving surgery as standard of care to reduce local recurrence risk and improve survival 3
• The European Society for Radiotherapy and Oncology recommends regional nodal irradiation if lymph nodes are found to be positive 2

Systemic Therapy Considerations

Endocrine Therapy

• The American Society of Clinical Oncology recommends adjuvant endocrine therapy for all hormone receptor-positive breast cancers 3, 2
• For premenopausal women, the European Society for Medical Oncology recommends tamoxifen for 5-10 years as a standard option 3
• For higher-risk disease, the St. Gallen consensus recommends considering ovarian function suppression plus an aromatase inhibitor 1, 3

Chemotherapy Decision

• The American Society of Clinical Oncology recommends using genomic testing to guide chemotherapy decisions for T1c, node-negative tumors 4
• If genomic testing shows high recurrence risk, the National Comprehensive Cancer Network recommends adjuvant chemotherapy followed by endocrine therapy 1, 2

Follow-up Recommendations

• The European Society for Medical Oncology recommends regular follow-up visits every 3-4 months in the first 2 years, every 6 months from years 3-5, and annually thereafter 5
• The American College of Radiology recommends annual ipsilateral and contralateral mammography with ultrasound 5
• The National Osteoporosis Foundation recommends regular bone density evaluation for patients on aromatase inhibitors 5, 3