Scientists are working on body’s defense system to fight cancer for last 100 years, but the progress in this field has been exciting in the last few decades, producing discoveries with promising results. Immunotherapy is a new approach to cancer treatment which aims to unmask the life-threatening disease. It stimulates a patient’s immune system to target and then kills cancer cells.
Understanding cancer immunotherapy and immune system
Immunotherapy is an anti-cancer therapy that uses the body’s own immune system to fight a life-threatening disease like cancer.
The immune system can identify cancer cells as abnormal cells and tries to against a tumor. It is a network of cells and organs which is formed to protect the body from infections, harmful chemicals, and abnormal cell development. The immune system or the body’s natural defense system recognizes the foreign substance such as a germ enters the body and attacks it to stop it from causing any harm to the body. White blood cells or lymphocytes are an important part of the immune system, and there are two types namely:
- B-cells- These cells help in fighting bacteria and viruses
- T-cells- These cells are helpful in controlling the immune system as well as help B-cells to make antibodies.
Due to its ability to detect and eliminate abnormal cells, the immune system effectively prevents cancer from developing and spreading to other parts of the body. In some cases, the body’s own defense system is incapable of fighting the abnormal cell growth; it may not be strong enough to prevent the growth of cancer cells.
Working of immunotherapy
There are different types of immunotherapy, and all have a different mode of action. Immunotherapy is considered to boost the immune system to work better against cancer cells or remove the barriers to the immune system that stops it to attack the cancer cells.
Immunotherapy and its type
Checkpoint inhibitors- There are checkpoints or complex signals that stop the immune cells from attacking and destroying normal tissue. Cancer cells utilize these checkpoints to slow down the immune response. The discovery in the field of cancer treatment is checkpoint inhibitors that block this ability of abnormal cells to use the checkpoints to escape from the immune system and reactivate T cells, which helps in fighting against these abnormal cells.
Ipilimumab is a checkpoint point inhibitors that have been found beneficial in treating kidney cancer, advanced melanoma. Pembrolizumab and Nivolumab are also in the same group; these are approved to treat people with melanoma who failed to respond to other treatments. Furthermore, Nivolumab has been shown to be effective in treating patients with metastatic squamous non-small cell lung cancer who failed to respond to chemotherapy.
Immune stimulants- These helps stimulate the immune system to take a more active role in killing cancer cells.
When to use Immunotherapy?
Chemotherapy, radiotherapy, and surgery are still the primary use therapies for cancer treatment, but checkpoint immunotherapy is likely to benefit people with certain types of cancer:
- Head and neck
About Immunotherapy treatment
The length of the treatment depends upon:
- The type of cancer
- The cancer stage
- The type of immunotherapy
- How you respond to therapy
- The side effects of immunotherapy you may experience
Checkpoint inhibitors are given intravenously via injections. In some cases, more than one type of immunotherapy drug is recommended for ill cancer cells.
Side effects of Immunotherapy
Side effects of immunotherapy depend on the type of therapy a patient receives and how the patient’s body responds towards the treatment. The side effects of checkpoint inhibitors are different from other cancer therapies. Some of the common side effects of checkpoint inhibitors include skin rash, diarrhea, fatigue, dry eyes, joint pain, abdominal pain, etc. The rare ones include changes in vision, yellowing of the eyes, headaches, thyroid-related issues, severe abdominal pain, and shortness of breath and coughing.