Background
Laryngeal cancer is a generic term that includes carcinoma of the supraglottic, glottic, and subglottic structures. Squamous cell carcinoma (SCC) is the most common pathology, but primary laryngeal adenocarcinoma, chondrosarcoma, lymphoma, and plasmacytoma have also been described. [1, 2] The median age for diagnosis is 65 years of age. [3] According to the American Cancer Society's estimates, there will be about 13,5430 new cases of laryngeal cancer and about 3620 people (2890 men and 730 women) will die from laryngeal cancer in the United States in 2016. [9]
Note the radiograph below for anatomical information.
Lateral radiograph of the neck showing the different structures of the larynx: a, vallecula; b, hyoid bone; c, epiglottis; d, pre-epiglottic space; e, ventricle (air-space between false and true cords); f, arytenoid; g, cricoid; and h, thyroid cartilage.
Laryngeal Cancer Staging
Laryngeal cancer staging is based on the subsite involved and the extent of disease. The larynx has 3 subsites, as follows:
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Supraglottis: The supraglottis extends from the epiglottis superiorly to the true vocal folds inferiorly. This subsite includes the epiglottis, aryepiglottic folds, arytenoids, and false vocal folds.
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Glottis: These are the true vocal folds.
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Subglottis: This extends from the true vocal folds superiorly to the first tracheal ring inferiorly.
The American Joint Committee on Cancer (AJCC) uses the TNM classification to define laryngeal cancer, as seen in the table below. [4]
Table 1. Tumor, Node, Metastasis (TNM) Classification Description (Open Table in a new window)
Laryngeal Subsite |
Primary Tumor (T) |
Regional Lymph Nodes (N) |
Distant Metastasis (M) |
Supraglottic |
T1: Tumor limited to one subsite of supraglottis with normal vocal cord mobility T2: Tumor invades mucosa of more than one adjacent subsite of supraglottis or glottis or region outside the supraglottis without fixation of the larynx T3: Tumor limited to larynx with vocal cord fixation and/or invades any of the following: postcricoid area, pre-epiglottic space, paraglottic space, and/or inner cortex of thyroid cartilage T4a: Tumor invades through the thyroid cartilage and/or invades tissues beyond the larynx (eg, trachea, soft tissues of neck including deep extrinsic muscle of the tongue, strap muscles, thyroid, or esophagus) T4b: Tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures |
N1: Metastasis in a single ipsilateral lymph node, ≤3 cm in greatest dimension N2a: Metastasis in a single ipsilateral lymph node, >3 cm but ≤6 cm in greatest dimension N2b: Metastases in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c: Metastases in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3: Metastasis in a lymph node, >6 cm in greatest dimension |
M0: No distant metastasis M1: Distant metastasis |
Glottic |
T1a: Tumor limited to one vocal cord T1b: Tumor involves both vocal cords T2: Tumor extends to supraglottis and/or subglottis and/or with impaired vocal cord mobility T3: Tumor limited to the larynx with vocal cord fixation and/or invasion of paraglottic space and/or inner cortex of the thyroid cartilage T4a: Tumor invades through the outer cortex of the thyroid cartilage and/or invades tissues beyond the larynx T4b: Tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures |
N1: Metastasis in a single ipsilateral lymph node, ≤3 cm in greatest dimension N2a: Metastasis in a single ipsilateral lymph node, >3 cm but ≤6 cm in greatest dimension N2b: Metastases in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c: Metastases in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3: Metastasis in a lymph node, >6 cm in greatest dimension |
M0: No distant metastasis M1: Distant metastasis |
Subglottic |
T1: Tumor limited to the subglottis T2: Tumor extends to vocal cord(s) with normal or impaired mobility T3: Tumor limited to larynx with vocal cord fixation T4a: Tumor invades cricoids or through the outer cortex of the thyroid cartilage and/or invades tissues beyond the larynx T4b: Tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures |
N1: Metastasis in a single ipsilateral lymph node, ≤3 cm in greatest dimension N2a: Metastasis in a single ipsilateral lymph node, >3 cm but ≤6 cm in greatest dimension N2b: Metastases in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c: Metastases in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3: Metastasis in a lymph node, >6 cm in greatest dimension |
M0: No distant metastasis M1: Distant metastasis |
Table 2. Table 1 Tumor, Node, Metastasis (TNM) Classification Abbreviations (Open Table in a new window)
Stage |
T |
N |
M |
I |
T1 |
N0 |
M0 |
II |
T2 |
N0 |
M0 |
III |
T3 T1-3 |
N0 N1 |
M0 M0 |
IVA |
T4a T1-3 |
N0-2 N2 |
M0 M0 |
IVB |
T4b T1-4 |
N1-3 N2 |
M0 M0 |
IVC |
T1-4 |
N1-3 |
M1 |
For all tumor subsites, Tx designates tumors that cannot be assessed, T0 is used when no primary tumor exists, and Tis means carcinoma in situ.
Indications
Total laryngectomy is a surgical option for patients with advanced stage laryngeal cancer that includes 1) tumors with cartilage destruction and anterior spread outside the larynx, 2) posterior commissure or bilateral arytenoid joint involvement, 3) circumferential submucosal disease, and 4) subglottic extension with extensive invasion of the cricoid cartilage.
Surgical salvage can be considered for patients who fail radiation therapy or partial laryngectomy procedures. Total laryngectomy can also be considered in patients with extralaryngeal tumors that have invaded the larynx such as advanced thyroid and base of tongue cancers. Adenocarcinoma and other less common histologies are less radiosensitive than laryngeal squamous cell cancer, so laryngectomy should be considered over organ preservation therapy in these cases. Patients with radiation necrosis of the larynx and severe aspiration can also be offered total laryngectomy.
Contraindications
Contraindications for surgery include the presence of distant metastases or synchronous tumors that are incurable, poor systemic health resulting in high anesthetic risk, and tumor that encases bilateral common or internal carotid arteries.
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Lateral radiograph of the neck showing the different structures of the larynx: a, vallecula; b, hyoid bone; c, epiglottis; d, pre-epiglottic space; e, ventricle (air-space between false and true cords); f, arytenoid; g, cricoid; and h, thyroid cartilage.
Tables
Laryngeal Subsite |
Primary Tumor (T) |
Regional Lymph Nodes (N) |
Distant Metastasis (M) |
Supraglottic |
T1: Tumor limited to one subsite of supraglottis with normal vocal cord mobility T2: Tumor invades mucosa of more than one adjacent subsite of supraglottis or glottis or region outside the supraglottis without fixation of the larynx T3: Tumor limited to larynx with vocal cord fixation and/or invades any of the following: postcricoid area, pre-epiglottic space, paraglottic space, and/or inner cortex of thyroid cartilage T4a: Tumor invades through the thyroid cartilage and/or invades tissues beyond the larynx (eg, trachea, soft tissues of neck including deep extrinsic muscle of the tongue, strap muscles, thyroid, or esophagus) T4b: Tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures |
N1: Metastasis in a single ipsilateral lymph node, ≤3 cm in greatest dimension N2a: Metastasis in a single ipsilateral lymph node, >3 cm but ≤6 cm in greatest dimension N2b: Metastases in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c: Metastases in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3: Metastasis in a lymph node, >6 cm in greatest dimension |
M0: No distant metastasis M1: Distant metastasis |
Glottic |
T1a: Tumor limited to one vocal cord T1b: Tumor involves both vocal cords T2: Tumor extends to supraglottis and/or subglottis and/or with impaired vocal cord mobility T3: Tumor limited to the larynx with vocal cord fixation and/or invasion of paraglottic space and/or inner cortex of the thyroid cartilage T4a: Tumor invades through the outer cortex of the thyroid cartilage and/or invades tissues beyond the larynx T4b: Tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures |
N1: Metastasis in a single ipsilateral lymph node, ≤3 cm in greatest dimension N2a: Metastasis in a single ipsilateral lymph node, >3 cm but ≤6 cm in greatest dimension N2b: Metastases in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c: Metastases in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3: Metastasis in a lymph node, >6 cm in greatest dimension |
M0: No distant metastasis M1: Distant metastasis |
Subglottic |
T1: Tumor limited to the subglottis T2: Tumor extends to vocal cord(s) with normal or impaired mobility T3: Tumor limited to larynx with vocal cord fixation T4a: Tumor invades cricoids or through the outer cortex of the thyroid cartilage and/or invades tissues beyond the larynx T4b: Tumor invades prevertebral space, encases carotid artery, or invades mediastinal structures |
N1: Metastasis in a single ipsilateral lymph node, ≤3 cm in greatest dimension N2a: Metastasis in a single ipsilateral lymph node, >3 cm but ≤6 cm in greatest dimension N2b: Metastases in multiple ipsilateral lymph nodes, none >6 cm in greatest dimension N2c: Metastases in bilateral or contralateral lymph nodes, none >6 cm in greatest dimension N3: Metastasis in a lymph node, >6 cm in greatest dimension |
M0: No distant metastasis M1: Distant metastasis |
Stage |
T |
N |
M |
I |
T1 |
N0 |
M0 |
II |
T2 |
N0 |
M0 |
III |
T3 T1-3 |
N0 N1 |
M0 M0 |
IVA |
T4a T1-3 |
N0-2 N2 |
M0 M0 |
IVB |
T4b T1-4 |
N1-3 N2 |
M0 M0 |
IVC |
T1-4 |
N1-3 |
M1 |
