Mastectomy techniques and indications

🗺️ Anatomy - Blueprint for the Breast

• Muscles: Breast overlies Pectoralis major. Pectoralis minor is the key landmark for axillary node levels.
• Ligaments: Cooper's ligaments (suspensory); tumor invasion causes skin dimpling (peau d'orange).
• Blood Supply: Medial (Internal mammary a.), Lateral (Lateral thoracic a.).
• Nerves at Risk (Axillary Dissection):
  • Long thoracic n.: → Serratus anterior (winged scapula).
  • Thoracodorsal n.: → Latissimus dorsi.
  • Intercostobrachial n.: → Medial arm sensation.
• Lymphatics:
  • Axillary Nodes (~75%):
    • Level I: Lateral to pec minor.
    • Level II: Deep to pec minor.
    • Level III: Medial to pec minor.
  • Rotter's Nodes: Interpectoral.

⭐ The pectoralis minor muscle is the surgical landmark dividing the axillary lymph nodes into Levels I, II, and III for staging.

🔪 To Cut or Not To Cut: Mastectomy Indications

• Absolute Indications (BCT is contraindicated):

  • Inflammatory Breast Cancer (IBC)
  • Multicentric/multifocal disease (tumors in >1 quadrant)
  • Diffuse suspicious microcalcifications on mammogram
  • History of prior radiation to the chest/breast
  • Inability to achieve negative surgical margins after lumpectomy attempts

• Relative Indications (Mastectomy often preferred):

  • Large tumor-to-breast ratio leading to poor cosmetic outcome with BCT
  • Collagen vascular diseases (e.g., scleroderma, active lupus)
  • Patient preference over BCT

• Specific Scenarios:

  • Prophylaxis: High-risk mutations (BRCA1/2)
  • Paget's Disease: If an underlying mass is present or disease is extensive.
  • Recurrence: Local recurrence after initial BCT.

• Contraindications:

  • Metastatic disease (Stage IV) unless for palliation (e.g., bleeding/ulcerated tumor).
  • Patient refusal.

⭐ Inflammatory Breast Cancer (IBC) is a clinical diagnosis (peau d'orange, erythema) and is an absolute indication for mastectomy, typically after neoadjuvant chemotherapy. BCT is contraindicated.

🔪 Management - The Surgical Playbook

Mastectomy is the surgical removal of breast tissue for cancer treatment or prophylaxis. Axillary staging is a critical component for prognosis and treatment planning.

• Axillary Management:
  • Sentinel Lymph Node Biopsy (SLNB): Standard for clinically node-negative (cN0) axilla.
  • Axillary Lymph Node Dissection (ALND): For clinically positive (cN+) nodes or positive SLNB.

Mastectomy Technique Comparison Structures Removed: ✅ Yes, ❌ No

🩹 Complications - The Aftermath

• Early: Seroma (most common), hematoma, skin flap necrosis, infection.
• Late: Lymphedema (chronic arm swelling), chronic pain (Post-Mastectomy Pain Syndrome), phantom breast sensation.
• Nerve Injury:
  • Long Thoracic n.: → Winged scapula (Serratus Anterior m.).
  • Thoracodorsal n.: → Weak arm adduction (Latissimus Dorsi m.).
  • Intercostobrachial n.: → Medial arm numbness.

⭐ The intercostobrachial nerve is most commonly injured during axillary dissection, causing sensory loss to the medial arm and axilla.

⚡ Biggest Takeaways

• Modified Radical Mastectomy (MRM) is standard: removes breast tissue and axillary nodes (Levels I/II), sparing the pectoralis major.
• Indications: inflammatory breast cancer, large tumor, multicentric disease, or radiation contraindication (e.g., pregnancy).
• Long thoracic nerve injury (axillary dissection) → winged scapula (serratus anterior palsy).
• Thoracodorsal nerve injury → latissimus dorsi paralysis (weak adduction/internal rotation).
• Lymphedema is a major chronic risk of axillary lymph node dissection (ALND).