Understanding the Disorder

Key Glossary Terms

Laryngeal/Voice Box
Composed of vocal folds, muscles, and framework cartilages; key for voice, breathing, airway protection

Early Cancer
T1 = affects only one site on larynx, no spread, normal vocal fold motion; T2 = involves more than one site on larynx, vocal fold function abnormal but still moving

Advanced Cancer
T3 = complete non-movement of one vocal fold; T4=invades thyroid cartilage or structures outside of the voice box

TNM Staging
T, tumor type; N, lymph nodes involved; M, spread to other body parts or metastasis

Vocal Folds (also called Vocal Cords)
A pair of specialized tissues in the voice box that vibrates for sound production; comprised of ordered layers of epithelium, superficial lamina propria, vocal ligament, and thyroarytenoid muscle

Glossary

Advanced laryngeal cancer (carcinoma) is divided into four main stages, depending on how advanced it has become or how far it has spread.

Key Information

This staging system only applies to squamous cell carcinoma of the larynx, the most common type of laryngeal cancer.

Advanced Laryngeal Cancer	Normal Vocal Folds
Patient with advanced cancer on the left vocal fold (vf). The whitish cancerous lesion (*) extrudes into the glottis or opening between the right (R) and left (L) vocal folds. Reddish cancerous lesion extends towards the front of the left vocal fold. This picture was taken during surgery to remove the lesion; and endotracheal tube (tube) is behind the lesion.

Staging is based on three characteristics that describe the tumor and its extent (the "TNM" system):

T = Tumor characteristics
N = lymph Nodes spread
M = Metastatic tumor spread

Staging is important in treatment management. Staging the laryngeal cancer helps determine what type of treatment is most appropriate and what the patient's expected outcome is likely to be.

(For more information, see Laryngeal Atypia and Early Cancer.)

(For more information, see Laryngeal Atypia and Early Cancer.)

NOTE: If the tumor spreads to one of these two sites, even if the vocal fold(s) is not paralyzed, the tumor is classified as a T3.

Advanced laryngeal cancer has a high likelihood of spread to lymph nodes in the head and can also spread (metastasize) to distant sites in the body such as the lungs (although this is not common).

These features have prompted the classification of laryngeal cancers as to:

The letter "N" stands for the lymph node(s) in the neck. Lymph nodes are nodules of specialized tissues that are part of the body's system to monitor and/or "clean up" the body. N-staging describes whether any tumor has spread to these lymph nodes directly from the tumor through lymphatic channels.

There are four "N" levels, from N0 to N3.

N0 = Zero Lymph Nodes Involved No spread of the larynx tumor to the lymph node in either side of the neck	No cancer cells in lymph node
N1 = One Slightly Enlarged Lymph Node Has Cancer Cells One lymph node has cancer cells but is small in size, not bigger than 3 cm or 1.25 inches in diameter	3 cm in diameter
N2 = More than One Lymph Node Has Cancer Cells or Semi-Large Lymph Node Several lymph nodes with cancer cells on one or both sides of the neck A large node on one side: 3-6 cm or 2.5 inches	or 6 cm several lymph nodes
N3 = Large Lymph Nodes with Cancer Cells Lymph node with cancer cells; lymph node larger than 6 cm or 2.5 inches	Lymph node larger than 6 cm

"M" stands for metastasis of the larynx tumor, which means spread of cancer cells from the tumor to other parts of the body outside of the head and neck.

After the TNM description is made, different combinations are grouped together as stages. The four stages of larynx cancer used in the management of patients with larynx cancer are presented below.

(For more information, see Laryngeal Atypia and Early Cancer.)

Advanced Laryngeal Cancer

There are several types of cancers of the larynx. These cancers are typed based on the cells comprising the cancer.

Squamous cells are cells that form the lining of the mouth, throat, and voice box (larynx), as well as skin. When squamous cells lose their growth control and regulation, they may grow uncontrollably and start invading their surroundings – thus becoming cancerous. Approximately 95% of all laryngeal cancer is squamous cell carcinoma/cancer.

This type of cancer is thought to arise from chronic irritation and the resulting genetic changes in the cell. Chronic irritation can come from the following:

Note: Alcohol may contribute to the development of laryngeal cancer by reducing the function of the immune system and/or by reducing the nutritional status of individuals who use heavy amounts of alcohol on a regular basis. In addition, desiccation (excessive drying) of tissues chronically exposed to alcohol may increase the risk of cancer.

A less common type of cancer in the larynx is called verrucous carcinoma (named because of its warty appearance). Verrucous carcinoma can occur elsewhere in the head and neck, including the mouth. In the larynx, this cancer is:

As such, often this type of cancer can be treated by surgical removal of the tumor (surgical excision).

Note: The association of verrucous carcinoma with cigarette smoking and alcohol use is much less well established than squamous cell carcinoma (although invasive squamous cell carcinoma can sometimes be found within a verrucous cancer, a condition called a "hybrid" tumor).

Another uncommon type of cancer in the larynx originates in the salivary gland. Many small salivary glands provide mucous, lubrication, and other secretions to aid in speaking, swallowing, and breathing in the larynx. Chronic irritation, exposure to tobacco and alcohol, and other causes may lead to salivary gland carcinoma in the larynx.

Red Flag

Salivary carcinomas in the larynx may get quite advanced and can be just as troublesome and difficult to deal with medically as the much more common squamous cell cancer variety.

Another rare type of cancer than can occur in the larynx is cancer of the cartilages in the voice box framework, e.g., chondrosarcoma of the thyroid cartilage. (For more information, see Anatomy & Physiology of Voice Production.)

Other tumor types can occur in the larynx – although rarely. These include spindle cell carcinoma, lymphoepithelioma, undifferentiated cancers, neuroendocrine carcinoma, neurofibrosarcoma, and cancers of the lymphoid tissues called lymphoma (usually non-Hodgkin's lymphoma).

Increased amount and duration of smoking – cigarettes, cigars, and pipe smoking – directly increase risk for laryngeal cancer.

Heavy alcohol use, usually described as three or more alcoholic drinks, beers, or glasses of wine per day, increases laryngeal cancer risk.

Red Flag

The risk of laryngeal cancer in someone who smokes and drinks heavily is multiplicative exponential, not just additive. That is, cancer risk in a person who smokes and drinks is much greater than simply adding risk seen in an individual who smokes OR who drinks.

A third risk factor for laryngeal cancer is a history of a malignant tumor elsewhere in the head and neck.

Some viruses, such as particular strains of human papilloma virus (HPV), have been associated with laryngeal cancer. The impact on the diagnosis or treatment of a particular patient's tumor is not yet clear.

Backflow of stomach fluids to the throat and larynx (laryngopharyngeal reflux or LPR) has also been implicated in some laryngeal cancers. Current research investigations are studying the association of LPR and larynx cancer.

The average age at diagnosis for laryngeal cancer is approximately 60 years of age.

Males are more affected than females, with a ratio of approximately 2:1.

The incidence of all new head and neck cancer cases in the United States is approximately 50,000 per year. The incidence of new cases of laryngeal cancer is approximately 12,000 cases per year.

Over the years, it has become obvious that larynx cancer has increased as the use of tobacco and alcohol has increased.

Key Information

Better Detection Methods Have Led to Increased Diagnosis

Better methods of detection and evaluation of the larynx have identified advanced laryngeal cancer as the cause of death much more frequently than in previous decades and centuries, when doctors could not evaluate the throat and vocal folds visually.

Highlights

Symptoms