Laryngeal squamous cell carcinoma is a cancer that develops in the voice box, where cells in the flat lining of the throat grow out of control. This disease can affect your ability to speak, breathe, and swallow, and is most often linked to smoking and alcohol use.

What is Laryngeal Squamous Cell Carcinoma?

Laryngeal squamous cell carcinoma is a type of cancer that forms in the larynx, also known as the voice box. The larynx is a tube-like structure located in your throat, between the base of your tongue and your windpipe. It plays a vital role when you breathe, swallow, and speak. Inside the larynx are the vocal cords, which vibrate to produce sound when air passes through them.^[1]

This cancer develops when squamous cells — the thin, flat cells that line the inside of the larynx — begin to grow uncontrollably. These cells normally cover the surface of the vocal cords and other parts of the voice box. When they become cancerous, they multiply and invade nearby tissues, causing damage to your body.^[3]

Most laryngeal cancers are squamous cell carcinomas. In fact, nearly all cancers in this area begin in these flat, skin-like cells. Changes in laryngeal cells sometimes start as precancerous conditions, meaning the cells are abnormal but not yet cancer. The most common precancerous condition is called dysplasia, which means there is a higher chance that the abnormal cells will eventually turn into cancer.^[3]

The larynx is divided into three main sections, and cancer can start in any of them. The supraglottis is the upper part, above the vocal cords, and includes a flap of movable cartilage called the epiglottis. More than one in three laryngeal cancers — about 35% — begin here. The glottis is the middle part where the vocal cords are located. This is the most common site, with more than half of all laryngeal cancers — around 60% — starting in this region. The subglottis is the lower part, between the vocal cords and the windpipe. Only about 5% of laryngeal cancers, or about one in twenty, start here.^[1]

While squamous cell carcinoma is by far the most common type, there are other very rare forms of laryngeal cancer. These include cancers that start in the minor salivary glands, sarcomas that develop from the laryngeal skeleton, melanomas, and lymphomas. However, these account for only a small fraction of cases.^[4][5]

Epidemiology

Laryngeal cancer represents one-third of all head and neck cancers and is a significant health concern around the world. In the United States, approximately 12,500 to 13,020 people are diagnosed with laryngeal cancer every year. The disease causes about 3,910 to 4,000 deaths each year in the U.S.^[1][7]

This cancer does not affect all groups of people equally. Men are about five times more likely to develop laryngeal cancer than women. This difference may be because smoking and heavy alcohol use, both major risk factors for the disease, have historically been more common among men.^[1]

Age is another important factor. Laryngeal cancer occurs more frequently in people who are 55 years old or older. Younger people can develop the disease, but it is much less common in those under middle age.^[1]

Because laryngeal cancer is part of a larger group of cancers that affect the head and neck region, it shares many characteristics with other cancers in this area. People who have already had one head and neck cancer are at higher risk of developing another. About one in four people, or 25%, who have had a head and neck cancer will get it again.^[1]

Causes

The root causes of laryngeal squamous cell carcinoma are linked to substances and behaviors that damage the cells lining the voice box over time. There is a clear and strong connection between tobacco use, heavy alcohol consumption, and the development of squamous cell cancers in the upper parts of the breathing and digestive tracts, including the larynx.^[7][12]

Smoking cigarettes or using other tobacco products is the single most important cause of laryngeal cancer. The smoke irritates and damages the cells in the larynx repeatedly over many years. This ongoing harm can cause cells to change and become cancerous. The risk of laryngeal cancer decreases after a person stops smoking, but it remains higher than that of someone who never smoked, even many years later.^[7][12]

Drinking alcohol in large amounts, particularly more than one drink per day, also increases the risk of laryngeal cancer. When tobacco and alcohol are used together, the risk becomes even greater. This combined effect is more harmful than either substance alone. For people who have already been diagnosed with cancer and continue to smoke and drink, the chances of curing the cancer are lower, and the risk of developing a second tumor increases.^[7][12]

Some forms of human papillomavirus (HPV) — a virus that spreads through sexual contact — can also cause laryngeal cancer. HPV is better known for causing cervical and oropharyngeal cancers, but certain types can infect the cells of the larynx as well.^[1]

Risk Factors

Several factors increase the likelihood of developing laryngeal squamous cell carcinoma. Understanding these risk factors can help you recognize if you or someone you know may be at higher risk.

Smoking is the strongest risk factor. Whether you smoke cigarettes, cigars, or use pipes, all forms of tobacco greatly increase your chances of developing this cancer. The longer and more heavily you smoke, the higher your risk becomes.^[1]

Drinking alcohol frequently or in large amounts also raises your risk. People who drink more than one alcoholic drink per day have a higher chance of developing laryngeal cancer. When you combine smoking with heavy drinking, your risk increases even more dramatically than with either habit alone.^[1]

Your age matters too. Laryngeal cancer is more common in people aged 55 and older. While younger people can develop the disease, it is much less frequent in those under middle age.^[1]

Men are at higher risk than women. This difference is largely because smoking and heavy alcohol use have historically been more common among men. However, as these behaviors become more equal across genders, the gap may narrow over time.^[1]

If you have already had a head and neck cancer in the past, your risk of developing laryngeal cancer is higher. About 25% of people who have been treated for head and neck cancer will develop another cancer in this region.^[1]

Certain workplace exposures can increase risk. People who work with substances such as sulfuric acid mist, wood dust, nickel, asbestos, or chemicals used in manufacturing mustard gas are at higher risk. Those who work with machinery also face an increased chance of developing laryngeal cancer.^[1]

Infection with certain types of HPV is another risk factor. This sexually transmitted virus can cause changes in the cells of the larynx that may lead to cancer.^[1]

Symptoms

The symptoms of laryngeal squamous cell carcinoma can be easy to overlook at first because they often resemble the signs of a common cold or throat infection. However, when these symptoms persist for weeks without improvement, they may indicate something more serious.

The most common early symptom is hoarseness or a change in your voice that does not get better after two weeks. Because the cancer often starts in or near the vocal cords, it affects how your voice sounds. This persistent hoarseness is often what prompts people to see a doctor.^[1][7]

A sore throat or cough that does not go away is another frequent symptom. Many people assume this is just a lingering cold, but if it lasts for several weeks, it should be checked by a healthcare provider.^[1]

Pain or difficulty when swallowing can occur, especially when the cancer is in the upper part of the larynx. This symptom is called dysphagia. You might feel like food or liquids are hard to get down, or swallowing may be painful. In some cases, people feel referred pain in their ear, which happens because nerves in the throat are connected to nerves in the ear.^[1][7]

You may notice a lump in your neck or throat. This lump could be the tumor itself or a swollen lymph node, which is a small gland that can become enlarged when cancer spreads. Enlarged lymph nodes are more common when the cancer is in the supraglottic part of the larynx, which has many lymph vessels.^[1][7]

Trouble making voice sounds, known as dysphonia, can happen if the cancer affects how the vocal cords move. Your voice may sound weak, breathy, or strained.^[1]

Some symptoms are more serious and require immediate medical attention. If you have trouble breathing, a condition called dyspnea, you should seek help right away. Noisy, high-pitched breathing, known as stridor, is another urgent sign. Feeling like something is stuck in your throat — a sensation called globus sensation — or coughing up blood (hemoptysis) should also prompt you to see a doctor immediately.^[1]

When the cancer is very early and confined to the true vocal cords, which lack lymph vessels, it rarely spreads to lymph nodes. This is why early vocal cord cancer is often detected because of hoarseness before it has a chance to spread. However, if the cancer extends above or below the cords, lymph node involvement becomes more likely.^[7][12]

Prevention

While not all cases of laryngeal squamous cell carcinoma can be prevented, there are several steps you can take to lower your risk significantly.

The most important action you can take is to avoid tobacco in all its forms. If you smoke cigarettes, cigars, or pipes, or if you use smokeless tobacco, quitting will dramatically reduce your risk of laryngeal cancer. The sooner you stop, the better. Even though the risk remains somewhat elevated compared to someone who never smoked, it does decrease over time after you quit.^[7][12]

Limiting alcohol consumption is also very important. If you drink alcohol, try to keep it to no more than one drink per day. The combination of smoking and drinking increases your risk much more than either behavior alone, so reducing or eliminating both is the best strategy.^[1]

If you work in an industry where you are exposed to harmful substances such as asbestos, wood dust, nickel, sulfuric acid mist, or chemicals used in manufacturing, make sure to follow all safety guidelines. Use protective equipment such as masks and respirators to reduce your exposure to these substances.^[1]

Getting vaccinated against HPV can help prevent infections with certain types of the virus that can cause laryngeal cancer. The HPV vaccine is typically given to preteens, but it can also be given to older adolescents and adults who were not vaccinated earlier.^[1]

If you experience persistent symptoms such as hoarseness, a sore throat, or a cough that lasts more than two weeks, see a healthcare provider. Early detection of laryngeal cancer greatly improves the chances of successful treatment and can help preserve your ability to speak and swallow.^[1]

Pathophysiology

The pathophysiology of laryngeal squamous cell carcinoma involves a series of changes in the normal cells that line the larynx. These changes happen gradually over time, often as a result of long-term exposure to harmful substances like tobacco smoke and alcohol.

The larynx is made up of cartilage, ligaments, and muscles. It is divided into three main regions: the supraglottis, glottis, and subglottis. The inside of the larynx is lined with squamous cells, which are flat, thin cells similar to the cells on the surface of your skin. These cells normally grow, divide, and die in an orderly way. However, when they are repeatedly damaged by irritants such as cigarette smoke, they can begin to change.^[3]

Before cancer develops, cells may go through a precancerous stage called dysplasia. In dysplasia, the cells look abnormal under a microscope, but they are not yet invasive. This means they have not yet started to spread into deeper tissues. However, if dysplasia is not treated, it can progress to true cancer over time.^[3]

Once cancer develops, the squamous cells grow out of control and form a tumor. As the tumor grows, it can invade nearby structures such as the vocal cords, surrounding tissues, and cartilage. This invasion damages the normal function of the larynx. For example, when the tumor affects the vocal cords, it can make them stiff or prevent them from moving properly, leading to hoarseness or loss of voice.^[3]

The way the cancer spreads depends on where in the larynx it starts. The supraglottic region has a rich network of lymph vessels, which are small channels that carry fluid and immune cells throughout the body. Because of this, cancers that start in the supraglottis often spread to the lymph nodes in the neck early in the disease. About 25% to 50% of people with supraglottic cancer already have lymph node involvement when they are first diagnosed. The precise number depends on how large the tumor is.^[7][12]

In contrast, the true vocal cords in the glottis have very few or no lymph vessels. This means that cancer confined to the vocal cords rarely spreads to lymph nodes at first. However, if the cancer grows and extends above or below the vocal cords, it can reach areas with lymph vessels and then spread to lymph nodes.^[7][12]

Subglottic cancers, which are quite rare, drain through specific membranes to the lymph nodes in front of and beside the windpipe, and sometimes to lymph nodes in the lower part of the neck and even the chest. This drainage pattern affects how the cancer spreads and where doctors look for signs of spread.^[7][12]

As the tumor grows larger, it can cause mechanical problems. It may block the airway, making it hard to breathe. It can also interfere with swallowing by blocking the passage of food and liquids. In advanced cases, the cancer may invade nearby organs such as the thyroid gland, the esophagus (the tube that carries food to the stomach), or even the spine.^[3]

At the biochemical level, cancer cells have abnormal DNA that causes them to grow and divide without the normal controls that keep healthy cells in check. They do not respond to signals that tell them to stop growing or to die. This allows the tumor to keep expanding and invading nearby tissues. The grade of the tumor, which describes how abnormal the cells look under a microscope, and the depth of invasion into surrounding tissues both affect how aggressive the cancer is and how likely it is to spread.^[7]