Hamartoma: What is it? Characteristics, Location, Symptoms, Diagnosis and Treatment

It forms when cells in the body begin to accumulate in one place.

But this distinction is somewhat murky because while many forms of hamartoma do not begin to grow in the same way as a tumor, they have the potential to do so.

The main distinction between these two types of growths appears to be whether the tissue grows spontaneously as a result of cell replication (tumors).

Also if it is formed from a mixed collection of tissue and cells from other parts of the body that accumulate in a single mass (hamartomas).

We do not know what causes hamartomas to form. But the answer could be that some people are genetically more likely to develop them because of the way genes affect cell multiplication.

Hamartomas can develop almost anywhere, but they are most common within the lungs. In fact, they represent the majority of forms of non-cancerous lung growth.

And although they often do not present serious problems, these lung growths can begin to compress the tissue of the lungs and cause breathing problems.

Also, they often form in the hypothalamus, which can interfere with your body’s ability to regulate hormones.

And hamartomas can also form in the kidneys or other vital organs or blood vessels , which can lead to a number of different complications.

They are made up of abnormal but not cancerous cells, similar to the cells that make up the tissue where they originate. Bruises can look similar to cancer on imaging studies, and for this reason, they can be very scary.

In some regions of the body, they may not cause any symptoms, or even regress in time, while in others it can cause complications.

They can also occur as part of syndromes that predispose people to cancer in several different organs.

Many times, there are no symptoms associated with a hamartoma and they are found incidentally when a test is requested for another reason, but when they do cause symptoms it is often related to the location where they occur.

Hamartomas are benign (non-cancerous) tumors that will not spread to other parts of your body.

Characteristics of the hamartoma

A hamartoma is a benign (non-cancerous) tumor that is made up of “normal” tissues found in the region where they grow.

For example, a pulmonary (lung) hamartoma is a non-cancerous tissue growth that includes fat, connective tissue, and cartilage found in the regions of the lungs.

The difference between hamartomas and normal tissue is that hamartomas grow in a disorganized mass. Most hamartomas grow slowly, at a rate similar to normal tissues.

This occurs commonly in men. While some are inherited, no one knows for sure what causes many of these growths to occur.

Many people have never heard of hamartomas, but they are fairly common tumors. Pulmonary hamartomas are the most common type of benign lung tumor, and benign lung tumors are quite common.


Hamartomas can appear almost anywhere on the body. Some of the more common areas include:

Lungs:  Pulmonary (pulmonary) hamartomas are the most common type of benign lung tumor.

They are usually found accidentally when a chest x-ray or chest CT scan is done for some other reason.

If they occur near an airway, they can cause an obstruction resulting in pneumonia and bronchiectasis.

Skin:  Hamartomas can appear anywhere on the skin, but they are especially common on the face, lips, and neck.

Heart:  As the most common heart tumor in children, hamartomas can cause symptoms of heart failure.

Hypothalamus:  Since the hypothalamus is in a closed space in the brain, symptoms due to pressure on nearby structures are quite common.

Some of these include seizures, personality changes, and the early onset of puberty in boys.

Kidneys:  Hamartomas can be found incidentally on imaging studies of the kidney, but occasionally they can cause symptoms of kidney dysfunction.

Spleen: Hamartomas in the spleen can cause abdominal pain.

Pulmonary hamartomas

Pulmonary hamartomas are the most common benign tumors found in the lungs and are often discovered accidentally when chest imaging is done for some other reason.

With the increasing use of CT screening tests for lung cancer in people at risk, it is likely that more people will be diagnosed with hamartomas in the future.

If you recently had a CT exam and your doctor thinks you might have a benign tumor, such as a harmartoma, learn what happens when you have a nodule on the exam and the chances that it is cancer.

Hamartomas can be difficult to distinguish from cancers, but they do have some distinguishing features.

A description of “popcorn calcification,” which means popcorn images on a CT scan, is almost diagnostic.

Calcification (calcium deposits that appear white on X-ray studies) is common. Cavitation , a central area of ​​tissue rupture seen on X-rays is rare.

Most of these tumors are less than four centimeters (two inches) in diameter.


Hamartomas may not cause any symptoms or may cause discomfort due to pressure on nearby organs and tissues. These symptoms will vary depending on the location of the hamartoma.

Symptoms of these types of growths are often difficult to recognize at first. And growth can continue for months or even years before obvious symptoms emerge.

Most forms are benign, which means they do not grow or become cancerous.

Therefore, it is unusual for someone with a hamartoma to develop the type of systemic symptoms that we associate with cancerous tumors. And many ways don’t lead to any noticeable symptoms at all.

But hamartomas can cause serious symptoms due to the complications that can arise. If the growth is in a blood vessel, as many are, it can begin to block blood flow through the blood vessel.

This can lead to dangerous cardiovascular problems like high blood pressure. And if the hamartoma is near a major artery in the heart, it can even be fatal.

Also, hamartomas can become infected or ruptured, which can lead to bleeding or tissue damage.

In most cases, doctors find hamartomas while investigating the cause of some of these complications, or even during an exam for an unrelated condition.


The diagnosis of a hamartoma will depend on where it occurs. Since they can appear similar to a malignant tumor (cancer) on images, a biopsy is often needed to confirm the diagnosis.

Hamartoma treatment

Many hamartomas don’t actually require any treatment. In fact, one of the biggest dangers when it comes to these types of growths is misdiagnosis.

Many doctors may mistake growths for dangerous tumors and recommend therapy to remove the tumor when unnecessary.

And many tumor treatments such as chemotherapy or radiation therapy can carry their own health risks for the patient.

Instead, doctors who identify a growth must order tests for different enzymes to see if the tumor is actually interfering with the body’s function.

And many doctors recommend careful monitoring of growth to make sure it doesn’t expand too quickly.

Treatment should focus on managing any of the symptoms that the growth might be causing, such as pain or bleeding rather than eliminating the growth.

But there are times when removal is necessary, such as when growth begins to block blood vessels or causes severe, recurring symptoms.

In that case, doctors can usually remove hamartomas quite easily with basic surgery.

It is often recommended that doctors test any growths they remove to make sure they are not actually cancerous tumors.

Treatment options for a hamartoma will largely depend on the location of the tumor and whether or not it is causing the symptoms.

If the hamartomas are not causing symptoms, your doctor may recommend that the tumor be left alone and observed over time.


There has been much discussion about whether hamartomas should be observed or removed surgically.

A diagnosis can usually be made using a combination of imaging tests and a fine needle biopsy, and that surgery should be reserved for people who have symptoms due to their tumor or for people who still have questions about the diagnosis.

Procedures, when needed for pulmonary hamartomas include:

  • Wedge resection (removal of the tumor and a wedge-shaped section of tissue that surrounds the tumor).
  • Lobectomy (removal of one of the lobes of the lung).
  • Pneumonectomy (removal of a lung).

In addition to hamartomas, there are many other types of benign lung nodules.

For some people, a hamartoma can be a sign of a genetic mutation that can increase the risk of some cancers, such as breast cancer and thyroid cancer.

It is important to speak with your doctor about any special tests that may need to be done if this is the case. Talking with a genetic counselor may also be recommended.