Main Manifestations of Functional Atypia
Changes in the functional activity of tumor cells are divided into two main forms. Overall, this atypia leads to severe organ dysfunction and systemic disruption of the body's homeostasis, recognized as tumor disease.
The following manifestations are distinguished:
- Hyperfunction
- Dysfunction
- Hypofunction
- Metaplasia
- Degeneration
Tumor Hyperfunction
This form is characterized by the production of substances inadequate to the current physiological needs of the body. This process can be carried out by individual cells or the neoplasm as a whole.
Most commonly, this phenomenon is observed in hormonally active neoplasms affecting endocrine glands.
Examples of tumors:
- Pheochromocytomas (tumors of the adrenal medulla).
- Corticosteromas and aldosteromas (tumors of the adrenal cortex).
- Insulinoma (tumor of pancreatic beta cells).
- Cancers of the thyroid, parathyroid, and other endocrine glands.
Dysfunction and Its Mechanisms
Dysfunction involves the acquisition of traits by cells that are completely uncharacteristic of normal autologous tissues—that is, the tissues from which the tumor originally developed.
Mechanism of Development: Tumor cells express genes that program the synthesis of specific proteins characteristic of completely different cell types.
Examples of manifestations:
- Poorly differentiated gastric carcinoma cells are capable of producing collagen.
- Lung cancer cells can produce biogenic amines or adenohypophyseal hormones.
Metastasis as a Fatal Property
Metastasis represents a typical form of growth atypia in tumors and one of the most dangerous properties of the malignant process. The essence of the process is the transfer of neoplastic cells a certain distance from the primary maternal node and the subsequent development of a tumor with the exact same histological structure in a new tissue or another organ.