The Greeks believed your thymus was home to your soul. In fact, thymus means “soul” in Greek. While no studies have proved that to be the case, your thymus does play an important role in your immune system.
What Is the Thymus Gland?
The thymus gland is a soft organ that is large in babies but begins to shrink after puberty. Once you reach adulthood, your thymus gland becomes relatively small.
Your thymus is a fully developed organ in utero. It’s one of a few that curl in on themselves and become smaller and less active as you get older.
Your thymus creates your T cells, which are a type of white blood cell. The proteins in your thymus help teach the T cells about which organs they're getting sent to. Your thymus prepares your cells to do a specific job for the remainder of their days.
Where Is The Thymus Gland?
Your thymus gland is in the upper part of your chest. It sits in the space between your lungs, behind your breastbone (sternum) and in front of your heart. This area is also home to your esophagus, blood vessels, and lymph nodes.
What Does the Thymus Gland Do?
Your thymus plays a major role in helping your immune system defend your body. The main thymus gland function is to process and teach your T cells how to identify and get rid of germs and other foreign substances.
The thymus and T cells
T cells are white blood cells. They're part of your immune system. They have to learn how to defend your body, which they do in your thymus gland.
These fighter cells form in bone marrow, the spongy material inside your bones. From there, they travel to your thymus gland. In the thymus, T cells mature into germ-fighting immune cells. They "learn" how to remember bacteria and viruses they come into contact with, and they use that information to attack any future germs they encounter.
Thymus hormones
Another essential thymus gland function is to produce hormones that control different functions around your body. The thymus makes:
- Thymopoietin. It helps your body produce T cells.
- Thymulin and thymosin. These hormones help your immune system make specialized immune cells.
- Thymic humoral factor. It helps your immune system run smoothly.
Thymus vs. Thyroid Glands
Your thyroid is an endocrine gland like the thymus. The thyroid is higher up in your body, in your neck. While both glands are a part of your endocrine system, they have different functions.
The thyroid gland is responsible for releasing hormones that control metabolism, whereas your thymus is responsible for T cells that affect your immune system.
Signs of Thymus Problems
Though your thymus is resilient, it can easily be damaged. It's harder for your thymus gland to bounce back after damage as you age. Viral infections and stress can damage your thymus.
When damage happens, you may notice symptoms like chest pain, since your thymus gland is in your chest. Shortness of breath and weight loss are other symptoms of a problem with your thymus. These symptoms may be a sign of an autoimmune condition or potentially thymus cancer.
There are other signs you should watch out for:
- Persistent coughing
- Trouble swallowing
- Dizziness and headache
- Swelling in your face, neck, or upper chest
Thymus dysfunction
These are some of the most common causes of thyroid problems:
DiGeorge syndrome. Children with this condition are born without a thymus gland, or their thymus isn't fully developed. DiGeorge syndrome causes a weak immune system that can't protect very well against infections.
Hypogammaglobulinemia. With this condition, you don't have enough immunoglobulins, antibodies (proteins) that help your body fight germs.
Myasthenia gravis. This autoimmune disease prevents nerves from sending signals to muscles. It makes muscles weak.
Pure red cell aplasia. It's a rare blood disorder. Your bone marrow doesn't make enough red blood cells, which leads to anemia.
Thymus cancer. This rare type of cancer grows in cells of the thymus gland. It can spread to other parts of your body.
Thymic involution. The thymus gland slowly shrinks as you get older. A smaller gland reduces your immune system's ability to protect you from infection.
Enlarged thymus symptoms
The thymus gland sits close to your lungs and the blood vessels in your chest. As it grows, it can put pressure on these structures and cause symptoms like:
- Shortness of breath
- Coughing
- Trouble swallowing
- Appetite loss
- Weight loss
- Chest pain
- Swelling in your face, neck, and upper chest
- Blue color to your skin or flushing of your face
- Dizziness
- Headache
What Conditions Affect Your Thymus Gland?
Many thymus disorders could affect this small gland in your chest. Knowing the signs and symptoms could help you identify a problem early and start treatment quickly.
Ectopic thymus. This condition causes your thymus to be somewhere other than your chest. An ectopic thymus is benign but often gets confused with a tumor. Depending on its location, it can cause complications for other organs nearby. These include:
- Decreased blood flow
- Discomfort or pain in the area
- Swelling
- Impaired thyroid function
Type 1 diabetes. Insulin plays a critical role in the growth of your thymus gland. You may have trouble with your thymus if you're born with type 1 diabetes. This can cause a weakened immune system and related problems.
Autoimmune disorders. A variety of autoimmune diseases are connected to thymus gland tumors. Conditions like myasthenia gravis, pure red cell aplasia, and hypogammaglobulinemia are linked to thymus gland problems.
Ulcerative colitis, rheumatoid arthritis, and lupus are other autoimmune disorders linked to problems with your thymus.
Thymoma (thymus cancer). This type of cancer is rare, but multiple treatment options are available if it's caught early. Thymus cancer happens when abnormal growths appear on your thymus gland. Left untreated, thymus cancer can spread to different body parts.
The two types of thymus tumors are thymomas and thymic carcinomas. These are both known as thymic epithelial tumors (TETs). Thymomas are slower-growing tumors that don't often spread beyond your thymus. Thymic carcinomas are more aggressive and grow and spread faster. They're also harder to treat. Around 1 in 5 TETs are thymic carcinoma.
Thymus gland cancer symptoms
Most people with thymus gland cancer don't have symptoms when they're diagnosed. But these symptoms are worth seeing your doctor about:
- Shortness of breath
- A cough that doesn't go away
- Chest pain
- A hoarse voice
- Swelling in your face, neck, upper body, or arms
Talk to your doctor if you think you have symptoms related to your thymus gland. It’s vital to catch thymus disorders early. Your doctor can refer you to the right specialists to create a strategic treatment plan.
Thymic hyperplasia
This condition happens when your thymus gland is inflamed. It's non-cancerous but can be linked to many types of medical conditions. These include thyroid issues or myasthenia gravis.
Thymus gland and myasthenia gravis
Your nerves signal your muscles to move by releasing chemicals called neurotransmitters. Those chemicals fit into receptors on the surface of muscle cells the way a key fits into a lock. In myasthenia gravis, your immune system makes antibodies that destroy receptors. This prevents your muscles from receiving nerve signals. Eventually, muscles become weak.
Normally, the thymus gland is big in childhood and gets smaller as you age. In some adults with myasthenia gravis, the thymus gland stays big. People with this condition are more likely to have thymomas. Usually, these thyroid tumors aren't cancer, but they can be.
Do You Have to Keep Your Thymus Gland?
The thymus gland can regenerate and bounce back after illnesses and viruses, but that doesn’t mean you need to keep your thymus gland once you become an adult.
A study showed that two molecules, IL22 and BMP4, play a part in the natural regeneration of your thymus gland. These molecules come from cells inside your thymus gland and promote repair and rebuilding.
The thymus gland is a critical part of your immune system. But most of its work happens during childhood and slows after puberty. The T cells created in your thymus gland mature at that point. Then they become useful in fighting for your immune system for the rest of your life.
If you start to have problems with your thymus gland or become at risk for thymomas, your doctor may consider removing your thymus. By adulthood, your thymus becomes less useful.
What Is a Thymectomy?
A thymectomy is surgery to remove your thymus gland.
About 10% of people with myasthenia gravis have a thymoma. This is a tumor on your thymus gland. Usually, these are benign (non-cancerous). But sometimes, they can be malignant (cancerous). A thymectomy can help prevent myasthenia gravis.
Doctors recommend this surgery for people over 60 years old who have slight or more intense weakness from myasthenia gravis. For those with slight weakness, a thymectomy might be especially important if the weakness makes them less able to breathe or swallow. They also suggest the surgery for anyone who has a thymoma.
Possible effects of thymectomy
Recent data has shown there might be more effects to this surgery than experts used to think.
In one study, researchers found that when you have your thymus gland removed, you may have a higher chance of death later in life from any cause. They found that people with a thymectomy were about twice as likely to die within five years, even if they had a condition where they needed the surgery, like myasthenia gravis.
The study showed that people who got a thymectomy might also face a higher risk of cancer. They were found to be twice as likely to get cancer within five years of the surgery, compared to those who still have a thymus. Cancer in people who had a thymectomy seemed to be harsher. It was also more likely to return after treatment, compared to those with a thymus.
While the study can't prove that a thymectomy directly causes cancer or other fatal conditions, the findings are still a concern for experts. Until there's more data, doctors are urged to think about the importance of keeping the thymus, when possible.
Thymectomy during childhood
Since the thymus is so important for immune system development during childhood, a thymectomy during childhood (before puberty) can also lead to issues. When this happens, people may have lower T cell numbers in the long run. These are white blood cells that fight germs and disease.
Children who had a thymectomy could also have a weakened immune response when they get vaccines.
Thymus Treatment
Most serious thyroid disorders, like cancer, have a variety of treatments, including:
- Surgery to remove the tumor
- Radiation, which uses high-energy X-rays to kill cancer cells or stop their growth
- Chemotherapy, strong medicines that kill cancer cells or stop them from dividing
- Hormone therapy, which blocks hormones that help the cancer grow
- Targeted therapy, which blocks proteins and signals cancer cells need to grow
Herbs for thymus gland
A few herbs that regulate the immune system have been investigated to see if they improve thymus function, including:
- Thymus vulgaris
- Portulaca oleracea
- Zataria multiflora
These and other herbs haven't been well-studied for thymus function. Plus, herbal supplements can sometimes cause side effects or interact with medicines you take. Talk to your doctor or pharmacist before you buy any supplement, to make sure it's safe for you.
Takeaways
Your thymus gland is an important part of your overall development. The main benefits come during childhood, when your thymus works through complex processes to support your immune system.
At the beginning of life, without a functioning thymus, your T cells wouldn't know what to do or where to go once they mature.
Later in life, there may be reasons to consider surgery to remove your thymus, but the removal may come with some risks of other conditions, like certain cancers.
Thymus Gland FAQs
At what age does the thymus disappear?
The thymus gland starts to get smaller in the first year of life. It loses volume at a rate of 3% each year until you reach middle age. After that, it shrinks at a rate of 1% per year. By age 85, this gland barely functions.
What happens if the thymus gland does not function properly?
Your thymus gland is an important part of your immune system. It makes germ-fighting T cells. If your thymus gland doesn't work well, you won't have enough T cells to protect your body from infection.
What autoimmune disease is linked to the thymus gland?
Myasthenia gravis is an autoimmune disease that affects the thymus gland. People with this condition develop tumors on their thymus gland.