Tumor. Thymoma is a type of cancer that begins in the thymus. Thymoma is generally a slow-growing tumor. The following links may provide more information: http://goo. Gl/mqtn1 and this one: http://goo. Gl/oetwz and this one: http://goo. Gl/yjnh5.
Well.... I don't mean to shock you, but it is a type of cancer or pre-cancerous tumor. The thymus is a gland that sits on/near the heart. It is largest and probably most active during childhood, and shrinks as we age. It is involved in developing specialized cells of the immune system. A thymoma is uncontrolled growth of the cells of the gland. The specific type can result in many different outcomes and rx.