Thymoma in Children

What Is Thymoma?

Thymoma is a rare tumor of the cells that cover the outside surface of the thymus. The thymus is a small organ in the upper chest under the breastbone. It is part of the lymph system and makes white blood cells, called lymphocytes, that help fight infection. Thymoma usually forms in the front part of the chest and is often found during a chest x-ray that is done for another reason. Thymoma is a slow-growing tumor that usually does not spread to the lymph nodes or to other parts of the body. Most children are diagnosed with thymoma at an early stage.

Other types of tumors, such as lymphoma or germ cell tumors, may form in the thymus but they are not considered to be thymoma.

What Are the Risk Factors for Thymoma in Children?

People who develop thymoma often have one of the following immune system diseases or hormone disorders:

What Are the Symptoms and Signs of Thymoma in Children?

Thymoma may cause any of the following signs and symptoms. Check with your child’s doctor if your child has any of the following:

Other conditions that are not thymoma may cause these same signs and symptoms.

How Is Thymoma in Children Diagnosed?

Tests to diagnose and stage thymoma may include the following:

  • Physical exam and history.
  • X-ray of the chest.
  • CT scan.
  • PET scan.
  • MRI.
  • Biopsy.

What Is the Treatment and Prognosis for Thymoma in Children?

Treatment of thymoma in children may include the following:

Treatment of recurrent thymoma in children may include the following:

  • A clinical trial that checks a sample of the patient's tumor for certain gene changes. The type of targeted therapy that will be given to the patient depends on the type of gene change.

The prognosis (chance of recovery) is better when the tumor has not spread. Childhood thymoma is usually diagnosed before the tumor has spread.

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Last updated Oct. 6, 2017