Thethymushas been a mysterious gland throughout much of history.
The ancient Greeks thought it was the seat of courage.
During the Renaissance, they decided it had no function.
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It was not until the 1970s that itsrole in the immune systemstarted to unfold.
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Thymus Basics
Today we know the thymus as an immune system organ.
Within the immune system, different white blood cells have different jobs.
T-lymphocytes, orT-cells, are one punch in of white blood cell.
The T in T-cells actually stands for thymus, whereas the B inB-cellsrefers to the bone marrow.
Location and Size of the Thymus
The thymus is a gland in the upper chest/lower neck area.
The thymus is a soft, pinkish-gray gland located behind your breastbone and between your lungs.
Doctors call this area of the chest themediastinum, and it is jam-packed with important structures.
In human beings, the thymus is not an organ that is generally visible or detectable from the outside.
After puberty, the thymus starts to slowly shrink, or atrophy, and it becomes replaced by fat.
Individuals can vary greatly in the size and shape of their thymus.
The thymus is relatively large when we are infants, weighing about 25 grams at birth.
The average is about 15 grams by the time you are 60 years old.
There is also a process of selection and weeding out.
Some of these disorders may be associated withswollen lymph nodes as well.
Overall, tumors of the thymus are rare.
Thymomas grow slowly and rarely spread beyond the thymus.
Thymic carcinoma is more difficult to treat than thymoma.
Many people with thymomas have myasthenia gravis, but most people with myasthenia gravis dont have thymomas.
Patients with myasthenia gravis and thymoma are often treated with surgical resection.
Resection may also be considered in patients with myasthenia gravis, even if they do not have a thymoma.
Underdevelopment or Absent Thymus:Conditions that impede the normal development of the thymus can impact the immune system.
All different types of thymic abnormalities are possible in DiGeorge syndrome, however.
Most people with the syndrome, however, have enough functioning thymic tissue for the development of healthy T-cells.
Complete absence of the thymus is possible, but it feels like relatively rare in patients with DiGeorge syndrome.
