Up to 50% of thymomas are asymptomatic, meaning they do not produce any symptoms or signs. Physicians may diagnose a thymoma when they perform an imaging study for another reason. In other cases, the tumor may cause symptoms related to the size of the tumor and the pressure it exerts on adjacent organs.
- Chest pain,
- shortness of breath, and
- cough are common symptoms when symptoms do occur.
The following symptoms and signs are less common but may occur:
- Night sweats
- Weight loss
Some cases may spread to the lining of the lungs or heart or even to tissues outside the chest. Less than 7% of cases spread outside the chest cavity. Thymic carcinomas are more aggressive types of tumors than thymomas and are more likely to spread both locally and distantly (metastasize) and to cause symptoms.