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Symptoms of Thymoma and Thymic Cancer

 Consult your doctor if you have shortness of breath or other symptoms of thymoma or thymic cancer.

Most thymic tumors are discovered after a person starts to have symptoms. These may be related to the tumor itself, or they may be part of a condition related to the cancer, but not caused directly by the tumor mass.

The thymus is in the middle of the chest, near the airways and certain blood vessels. Tumors in the thymus can press on nearby structures, causing symptoms such as:

The thymus is near the superior vena cava, the main blood vessel bringing blood from your head and upper body to your heart. Larger tumors that press on this vessel can cause symptoms of superior vena cava syndrome, which can include:

Paraneoplastic syndromes

Thymomas are often associated with symptoms that are not directly caused by the tumor mass itself pushing on surrounding structures.  For example, about 30% to 50% of people with thymomas also have myasthenia gravis (MG), a disease in which the immune system forms antibodies that block the chemical signals that stimulate the muscles to move. This may cause varying degrees of muscle weakness, double vision (from eye muscle involvement), or swallowing problems.

Other common paraneoplastic syndromesrelated to thymoma include red cell aplasia (causing low blood cell count), and hypogammaglobulinemia (low antibody levels).

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