What are the treatment options for early stage breast cancer?

Management of Early Stage Breast Cancer

Breast-conserving surgery (BCS) followed by radiation therapy is the preferred treatment option for most patients with early breast cancer, offering equivalent survival outcomes to mastectomy while preserving the breast. 1

Surgical Management Options

Breast-Conserving Surgery (BCS)

• BCS is the preferred local treatment option for the majority of early breast cancer patients 1
• Oncoplastic techniques should be used when needed to maintain good cosmetic outcomes in technically challenging cases 1
• Careful histological assessment of resection margins is essential with no tumor at the inked margin required for invasive cancer and >2 mm margins preferred for DCIS 1
• For DCIS, both BCS followed by whole breast irradiation or total mastectomy are acceptable treatment options 1

Mastectomy

• Indicated when BCS is not possible due to tumor size, location, or patient preference 1
• Breast reconstruction should be available and proposed to all women requiring mastectomy 1
• Immediate breast reconstruction should be offered to most patients, except those with inflammatory cancer 1
• The optimal reconstruction technique should be discussed individually, considering anatomic, treatment-related factors and patient preferences 1
• Non-high-risk patients who opt for bilateral mastectomy should be counseled that survival outcomes with BCS might be even better than with mastectomy 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 SLNs) when postoperative tangential breast radiotherapy is planned 1
• Axillary radiation is a valid alternative in patients with a positive SLNB, regardless of the type of breast surgery 1

Radiation Therapy

After Breast-Conserving Surgery

• Postoperative radiation therapy is strongly recommended after BCS 1
• Boost irradiation is recommended to reduce the risk of in-breast relapse in patients at higher risk of local recurrence 1
• Accelerated partial breast irradiation (APBI) is an acceptable treatment option in patients with a low risk for local recurrence 1

After Mastectomy

• Post-mastectomy radiation therapy (PMRT) is recommended for high-risk patients, including those with:
  • Involved resection margins
  • Involved axillary lymph nodes
  • T3-T4 tumors 1
• PMRT should also be considered in patients with 1-3 positive axillary lymph nodes 1

Regional Irradiation

• Comprehensive nodal irradiation is recommended for patients with involved lymph nodes 1
• After axillary lymph node dissection (ALND), routine axillary irradiation should not be done to the operated part of the axilla 1

Systemic Therapy Options

Hormone Therapy

• For hormone receptor-positive breast cancer, endocrine therapy is essential 2
• Tamoxifen is effective for the treatment of estrogen receptor-positive breast cancer 3
• In postmenopausal women, aromatase inhibitors like anastrozole may be used as an alternative to tamoxifen 4
• Caution should be exercised with tamoxifen as it may increase the risk of endometrial cancer and uterine sarcoma in women who still have their uterus 3

Chemotherapy

• Adjuvant systemic treatment should preferably start within 3-6 weeks after surgery 1
• For patients at substantial risk for systemic metastases, it is preferable to give chemotherapy followed by radiation therapy rather than radiation therapy followed by chemotherapy 5

Targeted Therapy

• Anti-HER2 targeted therapy is recommended for HER2-positive disease 2
• CDK4/6 inhibitors and PI3K inhibitors may be used for hormone receptor-positive disease 2
• PARP inhibitors are beneficial for BRCA1/2 mutation carriers 2

Special Considerations

Age-Related Considerations

• Age should not be the sole determinant for withholding or recommending treatment 1
• In women 70 years or older with early, estrogen receptor-positive breast cancer, lumpectomy plus tamoxifen alone (without radiation) may be a reasonable option in select cases 6

Fertility Preservation

• In younger premenopausal patients, fertility issues and fertility-preservation techniques should be discussed before initiating any systemic treatment 1

After Primary Systemic Therapy

• Surgery following primary systemic therapy (PST) should follow general rules for early breast cancer, considering baseline tumor characteristics and post-treatment outcomes 1
• If BCS is anticipated after PST, marking of the tumor site is essential, and pre/post-treatment breast assessment using MRI should be performed 1

Multidisciplinary Approach

• Treatment decisions should be based on tumor burden/location, biology (including biomarkers and gene expression), as well as the patient's age, menopausal status, health status, and preferences 1
• The management of early breast cancer requires a multidisciplinary team including medical oncologists, breast surgeons, radiation oncologists, radiologists, pathologists, and breast nurses 1
• Patients should be provided with comprehensive information and actively involved in all management decisions 1