Lymphadenectomy

Lymphadenectomy Basics - Node Know-How

• Definition: Surgical removal of lymph nodes (LNs) for cancer staging & locoregional control.
• Purpose: Diagnose nodal metastasis, regional control, guide therapy, prognostication.
• Types:
  • Sentinel LN Biopsy (SLNB): Biopsy of first draining LN(s); ↓morbidity. Uses dye/radioisotope (Tc-99m).
  • Regional LN Dissection (RLND): Removal of regional LNs (axillary, cervical etc.).
    • Radical: Complete removal.
    • Modified Radical: Spares key structures.
    • Selective: Specific LN levels.
• Nodal Yield: Min. LNs for staging (e.g., ≥12 CRC, ≥10 breast ALND).
• Skip Metastases: Mets bypassing proximal LNs.

⭐ SLN is the first LN draining a tumor; its status predicts regional node status (e.g., breast, melanoma).

Nodal Anatomy - Lymphatic Landscapes

• Lymphatic drainage follows venous system; vital for cancer staging & surgical approach.
• Sentinel Lymph Node (SLN): First node(s) draining a tumor. SLNB guides further nodal dissection.
• Key Nodal Basins:
  • Axilla: Levels I-III relative to pectoralis minor. Rotter's nodes (interpectoral).
  • Neck: Levels I-VII define anatomical compartments.
  • Mediastinum: IASLC map (e.g., paratracheal, subcarinal, hilar).
  • Stomach: Perigastric stations (JGCA classification).
  • Pelvis/Groin: Iliac, obturator nodes. Groin: Cloquet's node (deep inguinal).
• Major Ducts: Thoracic duct (drains ~75% body lymph to left venous angle); Right lymphatic duct (right upper quadrant).

⭐ Virchow's node (left supraclavicular) classically signals metastatic gastric cancer (Troisier's sign).

Procedural Pointers - Cutting to Cure

• Goal: Achieve R0 resection (microscopically negative margins), accurate staging.
• Types:
  • Sentinel Lymph Node Biopsy (SLNB): For clinically node-negative (cN0) patients.
  • Regional LND: For positive SLN or cN+.
  • Radical LND: Extensive, rare.
• SLNB Technique:
  • Tracer: Tc-99m colloid + blue dye.
  • Identify: Gamma probe & visual.

• Nerves (Axilla):
  • Long thoracic (serratus ant.).
  • Thoracodorsal (lat. dorsi).
  • Intercostobrachial (medial arm sensation) - often cut.
• Complications: Lymphedema, seroma, nerve injury.

⭐ In breast cancer, if SLNB shows 1-2 positive nodes without extracapsular extension, patients undergoing breast-conserving surgery with whole breast radiation may not require completion ALND (AMAROS/ACOSOG Z0011 criteria).

Complications & Management - Navigating Node Nightmares

• Immediate/Early:
  • Hemorrhage/Hematoma: Prompt surgical control.
  • Nerve Injury: Meticulous dissection crucial.
    • Examples: Spinal accessory (neck), long thoracic (axilla), recurrent laryngeal (thyroid/neck), obturator (pelvic).
    • Management: Physiotherapy; rarely surgery.
  • Lymphocele/Seroma: Observation, aspiration; sclerotherapy for persistence.
  • Wound Infection: Antibiotics, drainage.
• Late:
  • Lymphedema: Most common, debilitating.
    • Prevention: Sentinel Lymph Node Biopsy (SLNB) over completion dissection where appropriate.
    • Management: Complex Decongestive Therapy (CDT) - Manual Lymphatic Drainage (MLD), compression, exercises, skin care. 📌 DECS (Drainage, Exercise, Compression, Skin care)
    • Surgical: Lymphaticovenous anastomosis (LVA), vascularized lymph node transfer (VLNT) for refractory cases.
  • Chronic Pain/Paresthesia: Multimodal analgesia, physiotherapy.
  • Functional Deficits (e.g., shoulder stiffness): Early physiotherapy.

⭐ Lymphedema risk post-axillary dissection for breast cancer can be 20-30% with Axillary Lymph Node Dissection (ALND), reduced to <5-7% with SLNB alone_

High‑Yield Points - ⚡ Biggest Takeaways

• Sentinel Lymph Node Biopsy (SLNB) is key for staging melanoma & breast cancer; guides further dissection.
• Axillary Lymph Node Dissection (ALND) for positive SLNB or clinically positive axillary nodes in breast cancer.
• Radical Neck Dissection (RND) removes levels I-V nodes, SCM, IJV, & SAN; high morbidity.
• Modified Radical Neck Dissection (MRND) spares ≥1 non-lymphatic structures (SCM, IJV, SAN).
• Selective Neck Dissection (SND) targets specific at-risk nodal levels based on primary site.
• Common complications: lymphedema, seroma, nerve injury (e.g., spinal accessory).