Thymoma tumors are tumors that occur in the epithelial cells of the thymus. Epithelial cells are a type of cells that make up many glands in the human body.

The thymus is an organ that is part of the immune system whose sole responsibility appears to be production of T cells. It is located in the chest cavity near the heart and sternum. Thymoma tumors are usually benign, but in rare cases they can also be malignant.

Men and women are equally affected and diagnosis most commonly occurs in people who are between the ages of 30 and 40.

Signs & Symptoms

One common symptom of Thymoma tumors is that the surrounding organs become compressed by the mass of the tumor. This can result in difficulty swallowing or coughing and chest pain. There are also many autoimmune diseases that are associated with the presence of these tumors. The most common one is myasthenia gravis, or MG. Others include acute pericarditis, Addison’s disease, pure red cell aplasia, and Good’s syndrome.

Approximately one third to one half of patients with Thymoma tumors have no signs or symptoms. In these cases the tumors are only found coincidentally during chest x-rays or CAT scans which are performed for other reasons.

Diagnosis

Thymoma tumors are most often diagnosed because of the presence of an autoimmune disease. Once the tumor is identified a biopsy of the cells is done to determine if the tumor is type A, type B or type AB. Type AB Thymoma tumors are a combination of the cells found in type A and type B. From there it is classified using the Masaoka staging system. This system rates tumors based on their size and whether or not the tumor has invaded surrounding tissue.

Treatment

Treatment of Thymoma tumors depends on the size and stage of the tumor. Surgery is the standard treatment for Thymoma tumors. In cases where the tumor is very large chemotherapy may be used to reduce the size of the tumor prior to surgery being performed. In some cases the entire thymus is removed. In adults this surgery does not have a negative effect on the autoimmune system, but it is not generally performed on children. If the tumor is invasive and spreading follow up treatments of chemotherapy and radiotherapy may be required.

Prognosis

Unfortunately the prognosis for late stage Thymoma tumors is not very good. Late stage tumors that have already metastasized are difficult to treat. Early detection and proper diagnosis are the best defense in treating Thymoma tumors and ensuring the best possible prognosis.