What are the current treatment options for early breast cancer?

Current Treatment of Early Breast Cancer

The treatment of early breast cancer requires a multidisciplinary approach combining surgery (preferably breast-conserving surgery), radiotherapy, and systemic therapies tailored to tumor characteristics, with breast-conserving surgery followed by radiotherapy being the preferred option for most patients with early breast cancer. 1

General Treatment Principles

• Treatment decisions should be based on tumor burden/location (size and location of primary tumor, number of lesions, extent of lymph node involvement), tumor biology (pathology, biomarkers, gene expression), as well as patient factors including age, menopausal status, general health status, and preferences 1
• Age alone should not determine treatment recommendations but should be considered alongside other factors 1
• In younger premenopausal patients, fertility preservation options should be discussed before initiating any systemic treatment 1
• Treatment should be delivered by a multidisciplinary team in specialized breast units/centers 1, 2

Surgical Management

Breast-Conserving Surgery (BCS)

• BCS is the preferred local treatment option for the majority of early breast cancer patients, with oncoplastic techniques used when needed to maintain good cosmetic outcomes 1
• For invasive cancer, no tumor at the inked margin is required; for ductal carcinoma in situ (DCIS), a 2-mm margin is preferred 1
• BCS followed by radiotherapy has been shown to provide better outcomes compared to mastectomy alone, including improved local control, distant control, and overall survival 3

Mastectomy

• Mastectomy may be necessary in cases of:
  • Tumor size disproportionate to breast size
  • Tumor multicentricity
  • Inability to achieve negative surgical margins after multiple resections
  • Prior radiation to the chest wall/breast or other contraindications to radiotherapy
  • Unsuitability for oncoplastic breast conservation
  • Patient preference 1
• Breast reconstruction should be offered to all women requiring mastectomy 1
• Immediate reconstruction should be offered to most patients, except those with inflammatory breast cancer 1

Axillary Management

• Sentinel lymph node biopsy (SLNB) is the standard of care for axillary staging in early, clinically node-negative breast cancer 1
• Further axillary surgery following a positive SLNB is not required in cases of low axillary disease burden (micrometastases or 1-2 positive sentinel nodes) when postoperative radiotherapy is planned 1
• Axillary radiation is a valid alternative to axillary lymph node dissection in patients with a positive SLNB 1

Neoadjuvant (Preoperative) Therapy

• A neoadjuvant approach should be preferred in subtypes highly sensitive to chemotherapy, such as triple-negative and HER2-positive breast cancers, especially in tumors >2 cm and/or with positive axilla 1
• Neoadjuvant therapy can downsize tumors to facilitate breast conservation in patients who desire it 1, 4
• For triple-negative and HER2-positive tumors >2 cm, systemic induction therapy is recommended regardless of the feasibility of optimal surgery 1

Adjuvant Therapy

Radiotherapy

• Radiotherapy following BCS decreases mortality and recurrence rates 1, 5
• Whole breast irradiation or total mastectomy are acceptable treatment options for DCIS 1

Systemic Therapy

• Choice of adjuvant systemic therapy depends on lymph node involvement, hormone receptor status, HER2 expression, and patient age and menopausal status 4, 5
• For hormone receptor-positive disease:
  • Endocrine therapy for 5-10 years is essential 4
  • In postmenopausal women, aromatase inhibitors like letrozole have shown superior disease-free survival compared to tamoxifen 6
• For HER2-positive disease:
  • Anti-HER2 targeted therapy should be offered 2, 4
• For triple-negative breast cancer:
  • Chemotherapy is the mainstay of treatment 4

Special Considerations

Ductal Carcinoma In Situ (DCIS)

• BCS followed by whole breast irradiation or total mastectomy are acceptable treatment options 1
• SLNB should not be routinely performed in DCIS, except in patients with large and/or high-grade tumors, especially when mastectomy is required 1

Risk-Reducing Surgery

• Risk-reducing surgery may be offered to women at very high risk, such as BRCA1/2 mutation carriers or those with previous chest irradiation for lymphoma 1
• Careful genetic assessment and psychological counseling are mandatory before undertaking risk-reducing surgery 1

Common Pitfalls and Challenges

• Patients may opt for bilateral mastectomy despite evidence showing that breast conservation with radiotherapy may provide equal or better survival outcomes 1
• Treatment decisions may be overly influenced by patient age rather than considering all relevant factors 1
• Fertility preservation options may be overlooked in younger patients 1
• Patients may not receive appropriate multidisciplinary care if not treated in specialized breast units 2

Patient Communication and Decision-Making

• Information on diagnosis and treatment options should be provided repeatedly, both verbally and in writing 1
• Patients should be actively involved in all management decisions 1
• The use of reliable, patient-centered information sources is recommended 1