Our own body's power against cancer: Learn about immunotherapy

When we hear the word "cancer," we all cringe a little. It's a very serious word. But medical science has advanced a lot more than it used to. New treatments are being discovered almost every day to cure and control cancer. Today, we're talking about a treatment that has revolutionized the world of cancer treatment and brought new hope to many people. That's immunotherapy.

So, simply put, what is immunotherapy?

Imagine that our body is like a country. There is a very capable and strong army to protect this country. We call this army the immune system . The soldiers in this army (that is, immune cells) patrol our body all day long. Their job is to find and destroy enemies from the outside (like viruses and bacteria) and traitors from within (like cancer cells).

Normally, this army is very good at identifying and destroying cancer cells. But sometimes, these cancer cells are very cunning. They disguise themselves and hide from our soldiers. Or, they send out signals that stop our soldiers from functioning.

How does this treatment work?

Immunotherapy helps our immune system in two main ways:

1. Training the immune system: We teach our immune cells to accurately recognize disguised cancer cells. That is, they remove the masks on the cancer cells and show them to the army, saying, "Here is the enemy."

2. Increase the production of cancer-killing cells: It helps the body produce a large number of immune cells (soldiers) that fight cancer. Then it is easier for a large army to win the battle than a small one.

This treatment is now used as a first-line treatment for many types of cancer, especially for cancers that have spread to other parts of the body (metastatic). It is sometimes given in combination with other treatments, such as chemotherapy.

What are the main types of immunotherapy?

There are different types of immunotherapy, each of which uses different parts of our immune system to attack cancer.

1. Checkpoint Inhibitors

Our immune system is a very powerful thing. If it goes overboard, it can even damage our healthy cells. That's why our bodies naturally have a system of "checkpoints" or "brake" systems. When an immune cell (e.g., a T cell) is about to attack a cancer cell, the cunning cancer cell steps on this "brake" and disables the immune cell.

What a drug called a Checkpoint Inhibitor does is release the "brake" that the cancer cell has stepped on. Then our immune cells can get back to work. That means they can continue to destroy cancer cells.

This treatment method is used for very advanced cancer cases.

2. Adoptive Cell Therapy

This is like taking our soldiers out of the military, sending them to a special training camp, giving them superpowers, and sending them back into battle. Here, doctors take some of your own immune cells (T-cells) from your body and grow them in a lab.

• CAR T-cell therapy: Here, T-cells are genetically modified in the lab to have special "eyes" (receptors) that can recognize cancer cells. These super-powered T-cells are then made in large numbers and reintroduced into the body. These go directly to and destroy the cancer cells.
• Tumor-infiltrating lymphocytes (TIL) therapy: Taking a few immune cells (TILs) from within or around a tumor, growing them in large numbers in a lab, and then giving them back to the body. These cells are then able to fight the cancer successfully.

3. Monoclonal Antibodies

Antibodies are another important part of our immune system. They attach to foreign cells and mark them as "here's an enemy" for other immune cells to see. Monoclonal antibodies are artificial antibodies made in a lab that specifically target cancer cells. They're like GPS-guided missiles. They can:

• Block proteins needed for the growth of cancer cells.
• They attach to cancer cells and signal the immune system to destroy them.
• Deliver toxic or radioactive substances directly to cancer cells (Targeted delivery).

4. Cancer Vaccines

This is not like the vaccines we usually get to protect against viral diseases. These vaccines are given after cancer has developed. What this vaccine does is use parts of cancer cells to train our immune system to recognize cancer.

5. Immune System Modulators

These are drugs that generally boost the activity of our immune system. For example, proteins like `Cytokines`, `Interferons` and `Interleukins` are artificially produced and given as treatments. Drugs like `Thalidomide` and `Lenalidomide` also belong to this group.

Are there any side effects to this treatment?

Yes. Absolutely. Like any cancer treatment, immunotherapy has side effects. What happens here is that our immune system, which has become overactive, sometimes mistakes cancer cells for our own healthy cells and attacks them as well. This is called `immune-related adverse effects (irAE)`.

The most common side effects are:

• Feeling very tired (Fatigue)
• Itchy rash
• Diarrhea
• Nausea and vomiting
• Hormonal problems, such as low thyroid hormone levels.

These side effects are often mild, but can sometimes be serious. Therefore, it is important to inform your doctor immediately if you experience any unusual symptoms.

Important questions to ask your doctor

If you or someone in your family is recommended immunotherapy, it's important to be clear about what you're getting into. Don't be afraid to ask your doctor any questions you have. Here are some examples:

• What type of immunotherapy is recommended for me?
• Will I be given other treatments (like chemotherapy) along with this treatment?
• How do I get this treatment? How long does it take? How often do I need to take it?
• What are the possible short-term and long-term side effects of this? How can they be managed?
• What side effects should I notify you immediately if they occur?
• How will this treatment affect my daily life? Will I be able to go to work and exercise?
• How do we know if this treatment is successful?

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