Our immune system has the ability to identify and attack tumor cells. However, tumor cells, in turn, develop invisibility mechanisms to escape this attack and continue to proliferate.
One of these mechanisms is the expression of proteins on the surface of neoplastic cells called PD-L1, which bind to a receptor, PD1, on the surface of T lymphocytes (a type of cell in our immune system), thereby inactivating this way to the immune system.
From the knowledge of this mechanism, among others, the development of immunotherapy has arisen. We call immunotherapy the use of biological agents that act against these "invisibility mechanisms" of tumor cells and that allow us to reestablish our immune system so that it attacks tumor cells.
Types of immunotherapy
There are two types of immunotherapy, nonspecific immunotherapy, which seeks to produce a generalized response from our immune system (cytokines and anti-PD1 and anti-PD-L1 drugs) and specific immunotherapy (vaccines), which produces is response against a specific antigen of the tumor cell.
One of the advantages of immunotherapy is that, due to the memory of our immune system, the responses produced can be maintained over time, significantly increasing the survival of some patients.
These treatments are being used in cancer patients alone or in combination with chemotherapy to treat melanoma, lung cancer, kidney tumors, bladder carcinomas, and breast cancer.
What are the side effects of immunotherapy?
Due to this particular mechanism of action, tolerance to these treatments is generally better than chemotherapy treatments. However, these treatments can produce side effects derived from the immune response they trigger.
Sometimes, our immune system recognizes some of our tissues or organs as foreign and produces an inflammation. The symptoms will depend on the affected organ. One of the tissues that can be affected by immunotherapy is the skin, producing itching and dryness.
Another organ that can be affected is the intestine, producing colitis and therefore diarrhea. They can also cause hypothyroidism due to inflammation of the thyroid gland, pneumonitis (inflammation of the lung) and hepatitis (inflammation of the liver).
In recent years, immunotherapy has revolutionized the treatment of some tumors, improving their prognosis and survival. Immunotherapy has opened a new line of research in cancer treatment, with numerous clinical trials underway with new immunotherapeutic drugs and combinations.
If you are have any questions or comments about immunotherapy please contact us!
Article written by:
Dr. Natalia Eres. Medical Oncologist in the area of Ecomedicine and Holistic Oncology. Director of the Imohe Institute.