Aetiology:
Localized infection with human papillomavirus (HPV).
Clinical features:
- In the child (juvenile form): multiple lesions that may spread to the trachea and bronchi. Cases may regress at puberty.
- In the adult: less common and usually a single lesion.
Management:
Endoscopic removal using either suction diathermy or a CO2 laser. Surgical seeding of lesions within the larynx or trachea is common, and removal may be necessary for frequent recurrence.
Carcinoma (癌)
Aetiology:
Associated with cigarette smoking and high alcohol intake, although the latter is more important in causing piriform fossa carcinoma.
Clinical features:
Usually presents as persistent hoarseness. Dysphagia, chronic cough, stridor and referred otalgia may also occur. Occasionally a supraglottic tumour may present with metastatic neck nodes. The tumour may be evident on indirect laryngoscopy but endoscopic assessment and biopsy are mandatory before deciding on the appropriate treatment. A second primary (1%) in the upper aerodigestive tract should be searched for at this time.
Fine-needle aspiration cytology of any suspicious neck mass should also be undertaken. A CT scan will show any spread outside the larynx, or involvement of laryngeal cartilages.
Management:
Small (T1 and T2) carcinomas are best treated with primary radiotherapy, laryngectomy being reserved for post-radiation recurrences, larger (T3 and T4) lesions and primary tumours associated with neck nodes greater than 2cm in diameter. Primary endoscopic excision of laryngeal carcinomas with a carbon dioxide laser is now being undertaken by some surgeons.
Voice rehabilitation:
Following total laryngectomy the patient may be able to speak again by:
- Learning oesophageal speech (swallowed air is voluntarily regurgitated through the pharynx)
- Using an artificial larynx, which transmits vibrations into the pharynx and oral cavity while the patient articulates
- Surgical provision of a tracheo-oesophageal fistula, which is fitted with a button or valve. The button has a one-way flutter valve, which allows airflow from the trachea into the pharynx when the tracheostome is occluded. In selected patients this enables the development of good voice.
Patients require close follow-up. Recurrences can develop in the larynx, pharynx, stoma or neck. Further surgery or radiotherapy may be indicated. The expected 5-year survival for a T1 laryngeal cancer is about 95%. This falls to about 50% for T4 disease.
