Lymphatic Drainage of Larynx
Lymphatic drainage of larynx is clinically important because it determines:
- nodal metastasis
- prognosis
- staging
- neck dissection planning
Drainage differs significantly between:
- supraglottis
- glottis
- subglottis
Supraglottic Larynx
Supraglottis has rich lymphatic drainage.
Lymphatics pierce the thyrohyoid membrane and drain into:
- upper deep cervical nodes
- middle deep cervical nodes
Clinical Importance
Supraglottic carcinomas frequently metastasize early to cervical lymph nodes.
Bilateral nodal metastasis may occur, especially in epiglottic lesions.
Glottic Larynx
True vocal cords contain very few lymphatics.
Clinical Importance
Because of sparse lymphatic drainage:
- early glottic cancers rarely metastasize
- prognosis is relatively good
- hoarseness appears early before nodal spread occurs
Nodal metastasis usually suggests advanced disease extending beyond the vocal cord.
Subglottic Larynx
Subglottic lymphatics pierce the cricothyroid and cricotracheal membranes.
Drainage occurs into:
- prelaryngeal nodes
- pretracheal nodes
- lower deep cervical nodes
- mediastinal nodes
Clinical Importance
Subglottic cancers may spread inferiorly and metastasize to lower cervical or mediastinal nodes.
Comparative Overview
| Region | Lymphatic Drainage | Clinical Implication |
|---|---|---|
| Supraglottis | Rich | Early nodal spread |
| Glottis | Sparse | Best prognosis |
| Subglottis | Lower cervical and mediastinal | Inferior spread |
Clinical Correlation
The differing lymphatic drainage explains the distinct behaviour of laryngeal cancers.
For example:
- supraglottic cancers often present with neck nodes
- glottic cancers present early with hoarseness
- subglottic tumours may spread silently to lower nodes
Understanding these pathways is essential during:
- staging
- imaging interpretation
- radiotherapy planning
- neck dissection