Cancer Larynx ent

Carcinoma Larynx

Epidemiology:

  • Incidence: 2.63% of all cancers in India.
  • Gender: Males > Females (10:1 ratio). Increasing in females due to smoking.
  • Age: Mostly 40–70 years; occasionally 30s.

Aetiology

  • Tobacco & Alcohol: Major risk factors. Cigarette smoke contains benzopyrene.
    Synergistic Effect: Combined risk is 15-fold higher than individual factors (which are 2-3 fold).
  • Radiation: Previous neck irradiation for benign lesions/papilloma.
  • Genetic Factors: Familial aggregation seen (Japanese/Russian studies).
  • Occupational: Asbestos, mustard gas, petroleum products.

Surgical Anatomy (AJCC 2002)

Region Subsites
Supraglottis
  • Epiglottis (Suprahyoid & Infrahyoid)
  • Aryepiglottic folds (laryngeal aspect)
  • Arytenoids
  • Ventricular bands (False cords)
Glottis True vocal cords, Anterior commissure, Posterior commissure.
Subglottis From glottis to lower border of cricoid cartilage.

Histopathology

1. Types

  • Squamous Cell Carcinoma (90-95%):
    • Cordal (Glottic): Well-differentiated.
    • Supraglottic: Often Anaplastic.
  • Others (5-10%): Verrucous carcinoma, Spindle cell carcinoma, Malignant salivary gland tumours, Sarcomas.

2. Histopathologic Grade (G)

  • Grade 1: Well-differentiated.
  • Grade 2: Moderately differentiated.
  • Grade 3: Poorly differentiated.

Clinical Features by Site

1. Supraglottic Cancer

  • Frequency: Less common than glottic.
  • Site: Epiglottis/False cords > Aryepiglottic folds.
  • Symptoms (Silent initially):
    • Throat pain / Dysphagia.
    • Referred pain in ear.
    • Neck mass (Nodal metastasis).
    • Hoarseness is a LATE feature.
    • Halitosis, Weight loss (Late).
  • Spread:
    • Local: Vallecula, Base of tongue, Pyriform fossa, Pre-epiglottic space.
    • Lymphatic: Early & often Bilateral. Upper and middle jugular nodes.

2. Glottic Cancer (Most Common)

  • Site: Free edge/upper surface of anterior & middle 1/3 of vocal cord.
  • Symptoms:
    • Hoarseness is an EARLY sign (affects vibratory capacity).
    • Stridor/Obstruction (Late with oedema/fixation).
  • Spread:
    • Local: Anterior commissure (opp. cord), Vocal process/Arytenoid, Ventricle/False cord, Subglottis.
    • Lymphatic: Rarely seen (unless spread beyond membranous cord).
    • Prognosis: Cord fixation = Spread to Thyroarytenoid muscle (Bad sign).

3. Subglottic Cancer (Rare: 1-2%)

  • Symptoms: Stridor/Laryngeal obstruction (Earliest but often late presentation). Hoarseness is late (indicates upward spread).
  • Spread: Trachea, Thyroid gland, Cricothyroid membrane, Ribbon muscles.
  • Lymphatic: Prelaryngeal, Pretracheal, Paratracheal, Lower jugular nodes.

TNM Classification (AJCC 2002)

Primary Tumour (T)

Stage Description
T1 Limited to site of origin. Normal Cord Mobility.
(Glottic subsites: T1a = One cord; T1b = Both cords).
T2 Extends to adjacent site (e.g., Glottis → Supraglottis/Subglottis). Impaired Mobility (Not fixed).
T3 Limited to Larynx with Vocal Cord Fixation AND/OR invades Postcricoid, Pre-epiglottic, Paraglottic space, Minor thyroid cartilage erosion.
T4a Invades through Thyroid cartilage and/or tissues beyond larynx (Trachea, Tongue muscles, Thyroid, Oesophagus).
T4b Invades Prevertebral space, Carotid artery, or Mediastinum.

Regional Lymph Nodes (N)

  • NX: Cannot be assessed.
  • N0: No metastasis.
  • N1: Single ipsilateral, ≤ 3 cm.
  • N2:
    • N2a: Single ipsilateral, > 3 cm but ≤ 6 cm.
    • N2b: Multiple ipsilateral, none > 6 cm.
    • N2c: Bilateral/Contralateral, none > 6 cm.
  • N3: Any node > 6 cm.

Distant Metastasis (M)

  • MX: Distant metastasis cannot be assessed.
  • M0: No distant metastasis.
  • M1: Distant metastasis.

Stage Grouping

Stage TNM Profile
Stage 0 Tis N0 M0
Stage I T1 N0 M0
Stage II T2 N0 M0
Stage III
  • T3 N0 M0
  • T1 N1 M0
  • T2 N1 M0
  • T3 N1 M0
Stage IVA
  • T4a N0 M0
  • T4a N1 M0
  • Any T (T1-T4a) with N2 M0
Stage IVB
  • T4b Any N M0
  • Any T N3 M0
Stage IVC Any T Any N M1

Diagnosis

⚠ Clinical Dictum: Any patient in cancer age group with hoarseness > 3 weeks MUST undergo laryngeal examination.
  1. Indirect Laryngoscopy (IDL):
    • Appearance: Exophytic (Suprahyoid epiglottis), Ulcerative (Infrahyoid), Nodule/Ulcer (Cords).
    • Cord Mobility: Fixation = Deep infiltration (Muscle/Joint/Nerve).
  2. Flexible/Rigid Laryngoscopy: Outdoor procedure for documentation.
  3. Neck Examination:
    • Widening of laryngeal framework.
    • Tenderness (Perichondritis/Invasion).
    • Lymph nodes (Mobility, size, site).
  4. Radiology (CT/MRI):
    • Extent of tumour (Pre-epiglottic/Paraglottic space).
    • Cartilage destruction.
    • MRI useful for recurrent cancer after radiation.
  5. Direct Laryngoscopy: Essential for Hidden Areas (Infrahyoid epiglottis, Ant. commissure, Subglottis, Ventricle).
  6. Microlaryngoscopy: For accurate biopsy of small lesions.
  7. Supravital Staining: Toluidine Blue. Stains Carcinoma/CIS but not Leukoplakia. Helps select biopsy site.

Treatment

1. Radiotherapy (RT)

  • Indication: Early lesions (Mobile cords, No cartilage/nodal invasion).
  • T1 Glottic: 90% Cure rate. Voice preserved.
  • Exophytic Supraglottic (Tip of Epiglottis): 70-90% Cure rate.
  • Poor results in: Fixed cords, Subglottic extension, Cartilage invasion.

2. Surgery

A. Conservation Laryngeal Surgery (Preserves voice & airway):
  • Cordectomy: Excision of vocal cord (via Laryngofissure).
  • Partial Frontolateral Laryngectomy: Excision of cord + Anterior commissure.
  • Partial Horizontal Laryngectomy: Excision of Supraglottis (Epiglottis, false cords) above vocal cords.

B. Total Laryngectomy:

Removal of Larynx + Hyoid + Pre-epiglottic space + Strap muscles + Tracheal rings. Permanent tracheostome created.

Indications:

  • T3 lesions (Fixed cords).
  • All T4 lesions.
  • Thyroid/Cricoid cartilage invasion.
  • Bilateral Arytenoid involvement.
  • Posterior Commissure lesions.
  • Radiation failure.
  • Transglottic cancers.

3. Combined Therapy

  • Surgery + Pre/Post-operative Radiation.
  • Reduces recurrence; renders fixed nodes resectable.

4. Endoscopic Resection (CO2 Laser)

  • Precise excision under microscope.
  • Indications: T1 lesions of Mobile Cord or Epiglottis.
  • Advantages: Lower cost, shorter treatment, lower morbidity compared to open surgery/RT.

5. Organ Preservation

Induction Chemotherapy
+
Concurrent Radiotherapy

Outcome: Better locoregional control than Laryngectomy + Post-op RT. Preserves laryngeal function.

📚 Source: Dhingra ENT | Chapter 62

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