February 19, 2022
It is well known that cancers are commonly treated through chemotherapy, surgery or radiation therapy. These three treatment modalities are known as the three pillars of cancer treatment. However, the fourth pillar of cancer treatment is all set to be erected and that is immunotherapy.
The first thing that our immune system does when it encounters cancer cells is to launch an attack against them.
Nevertheless, upon fighting for some time, our immune system gets exhausted too. This leads to tumour formation and disease progression. Immunotherapy, as a treatment method, can awaken your immune cells and make them attack the cancer cells again.
Immunotherapy is the type of cancer treatment that enables your own immune system to attack the cancer cells present in your body. Immunotherapy is commonly administered to treat complex tumours, inoperable cancers, etc.
Immunotherapy uses multiple mechanisms to boost the body’s immune system against cancer:
- Educating the immune system to recognise and attack cancer cells
- Triggering immune cells to destroy cancer through complex immunological mechanisms
- Providing the body with additional components that enhance the immune response against cancer cells
While administering immunotherapy, oncologists focus on a unique parameter known as cancer biomarkers. A cancer biomarker could be defined as a molecule secreted by a tumour or a particular response of the body to the presence of cancer. These biomarkers are detected using tumour/blood samples. They play a significant role in treatment planning by helping oncologists understand cancers on a molecular level.
Types of Immunotherapy
There are different types of immunotherapy. The key ones include:
Monoclonal Antibody Therapy: Monoclonal antibodies are lab-generated antibodies that can work in many ways. They could work by blocking the division of cancer cells or triggering the immune system to attack and kill cancer cells.
Checkpoint inhibitors are a special class of monoclonal antibodies that work by blocking the proteins, which stop the immune system from acting against cancer cells.
T-cell Therapy: T-cell therapy involves modified T-cell, which is one of the immune cell types. The modified T-cells are injected back into the patient’s body, where they target and destroy cancer cells.
Oncolytic Virus Therapy: Oncolytic virus therapy is another form of immunotherapy wherein a special type of virus is injected into the body of the cancer patient. It kills the cancer cells without harming the healthy cells.
Cytokine Therapy: Cytokines are a group of special proteins that can stimulate the immune system against cancer by regulating the growth and division of cancer cells or triggering immune cells to attack the cancer cells. Lastly, cytokines also function by triggering the cancer cells to produce chemicals that attract the immune cells to find and attack them.
Cancer Vaccine: Cancer vaccines are used for both the prevention and treatment of cancer. These vaccines act by triggering the immune system to produce antibodies against cancer cells. HPV vaccination that is administered to prevent human papillomavirus (HPV) infection and thereby cervical cancer is an example of a cancer vaccine.
Advantages of Immunotherapy
Immunotherapy is a personalised treatment, i.e., immunotherapy is planned based on the biomarkers found in each patient. This treatment approach comes with a few advantages:
- Immunotherapy helps in treating a large number of cancers. This treatment is found to be effective among those patients who are resistant to chemotherapy and radiotherapy.
- Immunotherapy could also help patients achieve long term remission through the mechanism of “immunomemory”, wherein the immune system immediately launches an attack on cancer cells based on the memory of the previous encounter.
- Immunotherapy can help in achieving better clinical outcomes when combined with other treatments such as chemo or radiotherapy without disturbing the quality of life among the patients.
The side effects of immunotherapy are different from that of chemotherapy. If monitored carefully, these side effects are manageable.
Cancers are conquerable. When they are detected early, patients will have multiple treatment options along with excellent survival rates.
Studies are being constantly conducted in order to understand the best ways to harness the power of our immune system against cancer. With approaches like immunotherapy, it is now safe for us to say that we are one step closer to the cure.