The thymus is a small gland positioned behind the breastbone (sternum) in the mediastinal area that contains two divisions or lobes. It serves the body by being an organ of the immune system; specifically, the thymus is involved in the production of T-cells that aid in fending off antigens (foreign agents) and potentially infectious microorganisms. Charles Wood, M.D., states that thymomas are rare, slow-growing tumors that remain localized on the thymus gland. According to Sloan Kettering, they tend to manifest between the ages of 40 and 60 years, and most of these tumors (90 percent) are benign.
Cellular Etiology
Thymomas typically result when cells congregate on the outside of the gland. The thymus gland has three layers or divisions: beginning from the outside, the most external cover is the capsule; next, moving inward, is the cortex; and the internal core is known as the medulla. Thymomas are common on the external or capsule surface of the thymus. Additionally, the cells do not appear grossly abnormal; indeed, they look much like normal thymus cells. Pathologically, thymomas generally consist of epithelial cells and white blood cells (lymphocytes), which has led to thymomas also being referred to as lymphoepitheliomas when the majority of the thymoma has lymphocyte cells.
DNA Etiology
Frankly, the cause of this rare condition is not known. Perhaps there is an alteration in DNA material in the thymus cells; however, this is merely speculation.
Other
Again, there is no known cause for this disorder, and also no risk factors have been identified that might increase your chance for developing thymoma. Little is known about the etiology of this rare condition.
