The thymus is a gland associated with the immune system, and is the organ responsible for the development of T cells, which are essential for fighting infections and diseases.
Thymomas and thymic carcinomas affect the thymus, the gland located in the chest between the lungs. T lymphocytes are white blood cells that form a crucial part of the immune system, and the thymus is where these cells mature. It is largest and most active during childhood and adolescence. Following this period, the thymus becomes less active and is eventually it is replaced by fat tissue. This rare cancer is associated with the age group of 40 to 60 years old.
There are a number of conditions associated with thymic carcinoma, most notably autoimmune diseases. About 50 percent of people who develop thymus cancer also have myasthenia gravis, an autoimmune disease that weakens the muscles. Hypoglobulinemia, a disease that produces low levels of antibodies and makes it difficult to fight infection, is also associated with thymus cancer. Other diseases linked to this type of cancer are polymyositis, lupus erythematosus, rheumatoid arthritis, and thyroiditis.
In about half of all cases, thymus cancer does not produce any symptoms and is discovered in routine chest X-rays. When it does show symptoms, they include:
- Chest pain.
- Persistent cough or coughing up blood.
- Breathlessness or wheezing.
- Difficulty swallowing.
- Hoarse voice.
To diagnose this type of cancer, a series of tests can be performed, which may include chest X-rays, CT scans, and MRI & PET scans. Each of these techniques can show a different detail of the chest area and help to identify an abnormality. They can also be used to take a biopsy, which will be the ultimate test to determine whether the lesion is malignant or not. A biopsy may be done before or during surgery, and this will also help determine the stage of the tumour and the type of cancer.
Treatment will depend on the patient’s general health, as well as the stage and grade of the tumour. If the tumour is localized, it might be removed entirely during surgery. If it has spread beyond the local area and into the nearby organs, additional radiotherapy and chemotherapy may be needed. Chemoradiation is more effective than the individual use of chemotherapy or radiation therapy – it aims to kill the cancer cells while leaving healthy tissues relatively unharmed. It is used when the tumour has spread and cannot be surgically removed.