Like the causes, the pathogenesis of thymoma remains a mystery, but researchers do not lose hope of solving it and are considering various versions, including UV radiation and radiation.
The T-lymphocytes are produced by the thymus, their migration to peripheral lymphoid organs is ensured, and antibody production by B-lymphocytes is also induced. In addition, this lymphoid-glandular organ secretes hormones that regulate the differentiation of lymphocytes and the complex interactions of T cells in the thymus and tissues of other organs.
Timoma refers to epithelial tumors and grows slowly - with the proliferation of normal or modified medullary epithelial cells (similar to normal). Experts note that the epithelial cells that make up the malignant thymoma may not have typical signs of malignancy, which determines the cytological features of this tumor. And its malignant behavior, observed in 30-40% of cases, is an invasion of the surrounding organs and structures.
An analysis of the relationship of thymoma with other diseases showed that almost all of them are autoimmune in nature, which may indicate impaired tolerance of immunocompetent cells and the formation of a persistent autoimmune reaction (cellular auto-reactivity). The most common related condition (in a third of patients) is myasthenia gravis with thymoma. Myasthenia gravis is associated with the presence of autoantibodies to the acetylcholine receptors of neuromuscular synapses or to the enzyme muscle tyrosine kinase.
The correlation of tumors of this type with such simultaneously occurring autoimmune diseases as polymyositis and dermatomyositis, systemic lupus erythematosus, red blood cell aplasia (in half of the patients), hypogammaglobulinemia (in 10% of patients), bullous dermatoses (pemphigus), pernicious anemia or megal Addison’s disease), ulcerative colitis, Cushing’s disease, scleroderma, diffuse toxic goiter, Hashimoto thyroiditis, nonspecific aortoarteritis (Takayasu syndrome), Sjogren’s syndrome, hyperparaty rheoidism (excess parathyroid hormone), Simmonds disease (panhypopituitarism), Good's syndrome (combined B- and T-cell immunodeficiency).