For example, neoplastic islet cells in vitro can first increte insulin, then gastrin or cholecystokinin, and finally glucagon. Thus, tumors from cells of the APUD system (so-called apudoma) can be heterogeneous in terms of both cellular composition and secreted substances.
Moreover, both the primary tumor and its metastases can increte various hormones and mediators, the clinical manifestations of the APUD system disorder are usually diverse.
For example, tumors from enterochromaffin cells of the gastrointestinal tract cause the formation of stones in the gallbladder, lead to hypersecretion of gastric and pancreatic juice, hyperplasia of the mucous membrane, increase peristalsis, fibrosis of the myocardium and peritoneum, as well as necrotic changes in the skincurrent is often manifested by disorders of hormone processing. Therefore, tumor cells can secrete prohormones (for example, some insulinomas secrete significant concentrations of proinsulin)
Diagnosis of the disease is based on the data of a medical examination, history, increased levels of hormones in the blood and monoamine mediators in the urine. Treatment of tumors is only surgical. Medical therapy is ineffective.
With an untimely operation, the prognosis is extremely unfavorable. Tumors tend to quickly metastasize to internal organs, so chemotherapy or radiation treatment is used in most cases.
hormonally active apudoma increte excess concentrations of hormones or mediators and cause corresponding endocrine changes under the influence of excess peptide hormones secretion of gonadal hormones and corticosteroids is disturbed hormonally inactive apudoma usually do not manifest endocrine disorders hormonally inactive apudoma are noted that cause endocrine disorders.
For example, a pituitary adenoma (hormonally inactive) can cause the destruction of Lopressor and lead to the development of hypopituitarism ^Top.