The thymus is a lymphoid organ responsible for the production and maturation of T-lymphocytes. In the early development, precursor cells migrate from the bone marrow into the thymus where they mature into T-lymphocytes. T-lymphocytes are responsible for cellular immunity and inhibiting invasion of the body by foreign, infectious agents. Abnormalities of the thymus gland lead to immunological disease or cancers since T-cells aid in preventing abnormal cell growth that occurs in cancers, and in providing cellular immunity.
Thymoma
Thymoma is a disease state in which cancerous cells originate within the epithelial cells of the thymus, notes the Fox Chase Cancer Center. Thymoma enlarges the thymus and impairs the function of the immune system. Since T-lymphocytes mature in the thymus, cancerous cells within the thymus interfere with the maturation process of T-cells. This diminishes the ability of T-cells to fight infections, thereby leaving the individual susceptible to infection. Thymoma originating in the epithelial cells does not tend to metastasize to other parts of the body, but other forms of thymoma spread to other parts of the body causing thymic lymphoma. Thymomas are common in individuals who receive radiation therapy in the chest area, as well as individuals with myasthenia gravis.
Myasthenia Gravis
Myasthenia gravis is an autoimmune disease strongly associated with the growth of cancerous cells on the thymus. According to FindArticles.com, about 30 percent of thymomas occur in people with myasthenia gravis and about 15 percent of individuals with myasthenia gravis develop thymomas. Myasthenia gravis is characterized by the weakening of muscles, and increased susceptibility to viral and fungal infections. In myasthenia gravis, antibodies block or destroy the receptors for acetylcholine at the neuromuscular junction, thereby inhibiting the ability of muscles to contract. It is believed that an abnormality in the thymus and T-cell development results in T-cells that attack acetylcholine receptors, thereby disturbing neuromuscular transmission, notes the National Institute of Neurological Disorders and Strokes.
Thymic Hodgkin's Lymphoma
According to Path Consult, Hodgkin's lymphoma involves the lymph nodes, the thymus or both. Thymic lymphoma is radiologically presented as homogeneous, round, soft tissue located in the anterior of the mid line space between the lungs. Thymic Hodgkin's lymphoma infiltrates the thymus via the lymph nodes and lymphatic system. Thymic Hodgkin's lymphoma is greatly associated with myasthenia gravis, as well. Furthermore, thymomas can spread from the thymus to other parts of the body causing a non-Hodgkin's lymphoma.
