Laryngeal cancer

This is a boat. It rhymes with throat.

Definition

Cancer of the throat.

Pathophysiology

Laryngeal cancers are classified according to anatomy. Supraglottic above the red line; glottic between the two lines; subglottic below the green line.

Laryngeal cancers are almost exclusively squamous cell carcinomas. They are classified according to anatomy:

• Supraglottic - including the epiglottis, aryepiglottic folds, arytenoids, false cords... basically everything above the vocal cords
• Glottic - the vocal cords
• Subglottis - below the vocal cords

Epidemiology

Glottic is the most common accounting for 60% of cases of laryngeal cancer. Supraglottic accounts for a further 30% and subglottic accounting for the remaining 10%.

Risk Factors

• Smoking - by far the biggest risk factor. Really big. 10x that of non-smokers with pipe or cigar smoking actually worse than cigarettes
• Alcohol & smoking - there is a synergistic effect i.e. the risk is far more than simply adding the risk of smoking and alcohol together
• Diet
• Occupational exposure to carcinogens - asbestos, formaldehyde, nickel, sulphufric acid in particular
• HPV - implicated in upper airway tract cancer

Clinical Features

Glottic cancers mainly present with hoarseness (90%). The other two big symptoms are pain on swallowing (30-40%) and dysphagia (30%).

Supraglottic cancers tend to present late because there's a lot of space for them to take up before they start having an effect. Muffling of the voice, rarely hoarseness can present. Dysphagia that is painful occurs with aryepiglottic tumours. Metastatic neck nodes are occasionally the presenting feature.

Subglottic usually present with respiratory distress due to obstruction. If they expand upwards, they can present with hoarseness.