What are the treatment options for breast cancer?

Management of Breast Cancer

Breast cancer treatment requires a multidisciplinary approach involving surgery, radiation therapy, and systemic therapies tailored to tumor characteristics, with the goal of improving survival and quality of life. 1

Diagnostic Evaluation

• Initial assessment should include comprehensive staging to determine the extent of disease and guide treatment decisions 1
• Tumor characteristics that must be determined include:
  • Hormone receptor status (estrogen and progesterone receptors)
  • HER2 status
  • Tumor size and nodal involvement
  • Histological grade and proliferation markers (Ki67) 1, 2

Treatment Approach by Disease Stage

Early Breast Cancer (Stage I-II)

Surgical Options

• Breast-conserving surgery with radiation therapy or mastectomy are standard approaches for local control 1
• Axillary staging with sentinel lymph node biopsy is recommended for nodal assessment 1
• Multifocal disease may require mastectomy rather than breast conservation 1

Adjuvant Systemic Therapy

• Hormone receptor-positive disease:
  • Premenopausal women: Chemotherapy followed by tamoxifen 1
  • Postmenopausal women: Tamoxifen or aromatase inhibitors 1, 3
• HER2-positive disease:
  • Trastuzumab-based therapy in combination with chemotherapy 4
  • Standard regimens include doxorubicin, cyclophosphamide, and either paclitaxel or docetaxel 4
• Triple-negative disease:
  • Chemotherapy is the mainstay of treatment 1

Radiation Therapy

• Mandatory after breast-conserving surgery 1
• Post-mastectomy radiation indicated if risk factors for local recurrence are present 1
• Annual mammogram should be performed starting 6 months after treatment 1

Locally Advanced Breast Cancer (Stage III)

• Neoadjuvant (preoperative) therapy is standard approach 1, 2
• Options include:
  • Neoadjuvant chemotherapy
  • Neoadjuvant hormone therapy (for hormone receptor-positive disease)
  • Neoadjuvant radiotherapy 1
• Surgery follows response to neoadjuvant therapy 1
• Adjuvant therapy decisions based on residual disease and initial tumor characteristics 1

Metastatic Breast Cancer (Stage IV)

• The main treatment goal is palliation, with the aim of maintaining/improving quality of life and possibly extending survival 1
• Treatment should be personalized based on disease characteristics, prior therapies, and patient preferences 1
• Systemic treatment options include:
  • Endocrine therapy for hormone receptor-positive disease
  • Chemotherapy
  • Biological agents (trastuzumab, bevacizumab, lapatinib) 1
• For most patients, sequential single-agent chemotherapy provides equivalent survival with better quality of life compared to combination chemotherapy 1
• Radiation therapy plays an important role for:
  • Painful bone metastases
  • Brain metastases
  • Symptomatic soft tissue masses 1
• Bisphosphonates are indicated for bone metastases to reduce skeletal-related events 1

Treatment by Molecular Subtype

Hormone Receptor-Positive Disease

• Endocrine therapy is the cornerstone of treatment 1, 3
• Treatment duration typically 5-10 years 5
• Tamoxifen reduces risk of recurrence by 43-44% in high-risk women 3

HER2-Positive Disease

• Trastuzumab indicated for:
  • Adjuvant treatment of node-positive or high-risk node-negative disease
  • First-line treatment of metastatic disease in combination with paclitaxel
  • Single-agent treatment after prior chemotherapy for metastatic disease 4
• Cardiac monitoring required due to risk of cardiomyopathy 4

Triple-Negative Breast Cancer

• Chemotherapy is the primary systemic treatment option 1
• Represents 15-20% of all breast cancers and presents therapeutic challenges due to its aggressive nature 6

Special Considerations

Menopausal Status Assessment

• Critical for determining appropriate endocrine therapy 1
• Defined as:
  • Prior bilateral oophorectomy
  • Age ≥60 years
  • Age <60 years with amenorrhea for ≥12 months with appropriate hormone levels 1

Follow-up Care

• Regular evaluation of treatment results
• Screening for relapse
• Management of treatment side effects
• Psychosocial and professional rehabilitation 1
• Annual mammography for at least 10 years 1

Common Pitfalls and Caveats

• Adjuvant therapy should not replace optimal locoregional treatment 1
• Immediate breast reconstruction should not compromise delivery of appropriate adjuvant therapy 1
• Cardiac monitoring is essential during and after trastuzumab therapy due to risk of cardiomyopathy 4
• Tamoxifen increases risk of endometrial cancer and uterine sarcoma in women with intact uterus 3
• Pregnancy should be avoided during treatment with systemic therapies due to potential teratogenic effects 4