The anatomy used for speaking, breathing, and swallowing is known as the throat. When cells in the throat start to divide abnormally and rapidly the condition is called throat cancer. Most cancer of the throat is diagnosed as squamous cell carcinoma.
Types of Throat Cancer
Throat cancer is divided into two main types according to the location where the cancer is first found.
Pharyngeal cancer starts in the pharynx. The pharynx is the area of the throat that sits behind the mouth and nasal cavity and provides a passage for air and food and serves as a resonating organ to facilitate speech.
Laryngeal cancer occurs in the larynx, an organ found at the top of the neck. The larynx prevents food and foreign objects from entering the lungs by inducing coughing. The larynx also aids in breathing and is crucial to manipulating volume, pitch, and sound production. The pharynx is commonly referred to as the “voice box.”
Throat Cancer Facts
The American Cancer Society estimates that in the year 2020, 10,750 new cases of pharynx cancer and 3,750 of larynx cancer will be diagnosed. The good news is that the death rate for these cancers has been decreasing over the last 30 years. It is believed that a significant decrease in the amount of people smoking has contributed to the decline.
Throat cancer makes up 0.6% of all cancer deaths and according to the National Cancer Institute is ranked 22nd on the list of common cancers, representing 0.7% of all new cancer cases in the United States.
The median age at diagnosis is 66 and is much more common in men than women with 5.0 cases per 100,000 being men and only 1.1 cases in 100,000 in women.
Throat cancer that is diagnosed while localized has a 53% survival rate after five years.
Throat Cancer Symptoms
- Persistent sore throat that is not associated with strep or the flu.
- Burning or pain when swallowing.
- Vocal changes, such as a quieter or huskier sounding voice. This may also include difficulty in pronouncing certain words or the development of slurred speech.
- Lump on the neck can indicate a swollen lymph node which is common in people with throat cancer.
- Weight loss can be associated with difficulty in swallowing food and metabolism changes due to cancer.
- Difficulty moving the tongue and/or opening the mouth.
- Coughing that is persistent and may produce blood.
- Nosebleeds that are unexplained and frequent.
- Headache that lasts longer than two weeks and reoccurs.
Causes and Risk Factors
Doctors may not be able to determine the exact cause of every case of throat cancer but there are known behaviors and factors that increase the risk and can point to a likely cause.
- Human papillomavirus infection: Strains of HPV have been found in some pharyngeal tumors and doctors suspect the virus of playing a role in some cases.
- Use of tobacco products: Smoking, chewing tobacco and cigar use all increase the risk of throat cancer by damaging DNA directly and triggering a rapid growth of cells.
- Excessive use of alcohol: Heavy drinking contributes significantly to an increased risk of cancer. It is advised that women avoid more than one drink a day and men avoid more than two drinks a day.
- Poor nutrition: A diet high in red and processed meats, sugary drinks and processed foods increase the risk of all cancer, including throat cancer. A diet high in fruits and vegetables lowers the risk.
- Exposure to coal dust or asbestos: Research indicates an association between exposure to asbestos and coal dust and higher incidence of cancer.
- Genetic predisposition and age: Some genetic conditions increase the risk of throat cancer and men over the age of 65 are at an increased risk.
Environment Exposure and Throat Cancer
According to the American Cancer Society, exposure to wood dust, paint fumes, petroleum and plastics, as well as the chemicals used in metalworking and textile industries can increase the risk of throat cancer.
Studies of asbestos, a fiber used in manufacturing insulating material, have suggested a link between exposure to asbestos and throat cancer.
Hazardous Effect of Asbestos
In 1908, after the negative health effects of asbestos exposure was well known, insurance companies in the U.S. decreased coverage and increased premiums for asbestos workers. Despite warnings, asbestos mining and manufacturing continued.
U.S. asbestos consumption peaked in 1973 and by the late 1970’s the public was beginning to understand the health risks associated with asbestos exposure.
Labor and trade unions demanded healthier work conditions and liability claims against asbestos manufacturers forced a change in the market.
Medical evidence since 1930 has linked asbestos exposure to disease but legislation did not limit exposure for workers until the 1970’s.
In 2005 asbestos was banned throughout the European Union. The last United States asbestos mine was closed in 2002 but asbestos is still not banned in the U.S.
Asbestos and Cancer Diagnosis
Asbestos is a mineral that can be pulled apart into flexible fibers. Often the fibers are microscopic and can easily be swallowed or inhaled and the body has no way to break asbestos down or expel it. Asbestos fibers can become lodged in the throat and stay there long enough to cause inflammation and genetic changes that lead to cancer.
Exposure to asbestos is a risk factor for throat cancer and people with a known exposure should be screened regularly by a doctor.
Asbestos cancer is diagnosed by a referral from a family doctor to a specialist. The specialist may order imaging tests such as X-rays, CT scans, MRIs, and PET scans to look for tumors.
Blood tests are used to look for abnormalities in the cells.
Biopsy of a known tumor can help determine the type of cancer and the best treatment available. Chemotherapy, immunotherapy, surgery, and radiation therapy are all used to treat cancer. Often a multimodal therapy model is used, which combines available options to increase the odds of a favorable outcome.