March 29, 2017
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Thymoma facts

  • A thymoma is a type of thymus tumor or growth. It can behave in a benign fashion and is said to be non-invasive. It can behave in a malignant or cancerous fashion and is said to be malignant. A small percentage are frankly malignant and are called thymic carcinomas. Thymic tumors are uncommon.
  • The thymus gland is present in the front of the space between the lungs called the mediastinum. The thymus gland is most prominent during puberty, but then normally regresses in adulthood.
  • Thymomas are slightly more common in men than in women and are most frequently seen in persons between the ages of 40 and 60.
  • There are no known risk factors that predispose a person to developing thymoma.
  • Up to half of thymomas are asymptomatic, meaning they do not produce any symptoms or signs and are diagnosed when an imaging study of the chest is performed for another reason.
  • Chest pain, shortness of breath, and cough are common symptoms when symptoms do occur.
  • Many of patients with thymoma will have a so-called paraneoplastic syndrome. A paraneoplastic syndrome occurs preceding or concurrent with the discovery of the underlying cancer. These conditions accompany the cancer’s development but are not a direct result of the disease as might a lump or pain might be. They seem an indirect result of the cancer, and may or may not improve with the treatment of the underlying disease. The most commonly associated condition with thymoma is myasthenia gravis. Twenty percent of those with myasthenia gravis will be found to have a thymoma.
  • Thymomas are slow-growing tumors, and the prognosis is excellent when they are discovered in their early stages. 5 year survival for thymoma patients receiving modern treatment approaches 80%. Those with the more rare form of the disease called thymic carcinomas have a more aggressive disease with 5 year survival even with treatment of only about 40% on average.
  • Surgical removal is the mainstay of treatment.

What is thymoma?

A thymoma is an uncommon tumor of the thymus gland. The thymus is a gland located in the anterior mediastinum (the area between the lungs in the chest) that plays a critical role in the development of immune cells during childhood. The thymus gland enlarges during childhood, peaks in size at puberty (about 40 grams) and begins to shrink after an individual reaches puberty.

Normally, the thymus is made up of a combination of lymphoid cells (immune cells or lymphocytes) and lining cells (epithelial cells). Thymoma is a tumor that originates from the epithelial cells of the thymus. The term thymomic neoplasms is used to refer to tumors of the thymus, which consist of thymomas and thymic carcinomas. Thymic carcinomas are tumors of the thymus having cells with a markedly abnormal appearance under the microscope. Thymic carcinomas are more aggressive than thymomas (they are more malignant), but they account for only about 1% of thymic tumors.

Medically Reviewed by a Doctor on 3/16/2016



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