A cancer diagnosis changes everything, including the vocabulary patients suddenly need to understand. Surgery, chemotherapy, radiation, targeted therapy, and immunotherapy. Each one represents a different way of treating the same disease.
Immunotherapy has attracted growing attention over the past decade, and for good reason. It has changed treatment outcomes for patients who had very few options before. But it is also frequently misunderstood, either overhyped as a universal cure or dismissed as too new to trust.
This guide helps you decode what immunotherapy is, how it works, what kinds exist, and what patients should know before discussing it with their doctor.
To understand how immunotherapy works, it helps to know that cancer cells often evade the immune system by disguising themselves or suppressing immune activity. Immunotherapy is largely about reversing that.
What Is Immunotherapy for Cancer?
Most cancer treatments operate on a fairly direct principle: locate the cancer and destroy it. Immunotherapy takes a different approach. Rather than attacking tumour cells itself, it works on the immune system, either removing the barriers that cancer has put in place or giving immune cells the tools they need to act more effectively.
The immune system already knows how to find and destroy abnormal cells. Cancer itself is a malfunction of the immune system if you think of it. Immunotherapy is largely about undoing that malfunction.
Depending on the specific treatment, it might make cancer cells more visible to defence cells, block the proteins that tumours use to inhibit immune activity, or directly strengthen immune cells to improve their ability to recognise and respond to cancer.
How Is Immunotherapy Different from Chemotherapy?
| Chemotherapy | Immunotherapy |
|---|---|
| Targets cancer cells directly | Helps the body's natural defence mechanism target cancer cells |
| Effects stop when treatment ends | Immune responses may continue after treatment |
| Can affect healthy cells as well | Can work more selectively |
Chemotherapy targets fast-multiplying cells, which is effective but not accurate. Healthy tissue that divides quickly, such as that within the hair, gut, and bone marrow, is also affected unfortunately. Immunotherapy does not work that way.
How Does Immunotherapy Work?
The immune system relies on defence cells that continuously search for threats in the body.
Cancer cells may:
Hide from immune cells
Switch off immune responses
Create protective environments around tumours
Immunotherapy helps to overcome these challenges by:
Making cancer cells easier to recognise
Strengthening immune cell activity
Blocking signals that suppress immunity
Training immune cells to find and attack cancer
Types of Cancer Immunotherapy
Immunotherapy is not a single drug or a single approach. Several distinct treatment types exist, each working through a different mechanism.
1. Immune Checkpoint Inhibitors
Tumours can use certain proteins, called checkpoints, to trick immune cells to stop attacking. Generally, the rest of the body uses checkpoints to prevent the immune system from becoming overactive and damaging healthy tissue. Cancer exploits this system to protect itself.
Checkpoint inhibitors block these proteins, lifting the brake that cancer had placed on the immune system and allowing it to attack tumour cells again. They are among the most widely used forms of immunotherapy and are commonly used for:
Lung cancer
Melanoma
Kidney cancer
Bladder cancer
Head and neck cancers
2. CAR T-Cell Therapy
This treatment is a more intensive, personalised approach. Immune cells are collected from the patient, sent to a laboratory where they are modified to better recognise cancer cells, and then returned to the body. CAR T-cell therapy is currently used primarily in certain blood cancers.
3. Monoclonal Antibodies
These are proteins produced in a laboratory that are designed to attach to specific cancer cells. Once attached, they help the immune system locate and respond to those cells. Some monoclonal antibodies also deliver drugs or radiation directly to the tumour site.
4. Cancer Vaccines
These differ from the vaccines used to prevent infection. Therapeutic cancer vaccines are given to patients who already have cancer, with the aim of triggering an immune response against tumour cells. Research in this area is still advancing.
5. Cytokine Therapy
Cytokines are signalling proteins that the body uses to regulate immune activity. In certain cancers, synthetic cytokines are administered to strengthen or direct the immune response as part of a broader treatment plan.
Which Cancers Can Be Treated With Immunotherapy?
Immunotherapy is currently used in the treatment of several cancers, including:
Lung cancer
Melanoma
Kidney cancer
Bladder cancer
Liver cancer
Head and neck cancers
Hodgkin lymphoma
Certain blood cancers
Some colorectal cancers
Certain gastric cancers
Certain cervical cancers
Research continues across many other cancer types. Importantly, not every patient with these cancers will be a candidate for immunotherapy. Oncologists typically use biomarker testing to assess whether a patient's tumour is likely to respond.
Looking for Personalised Cancer Care?
Cancer treatment decisions depend on far more than the diagnosis alone. The stage, the biology of the tumour, the patient's overall health, and their treatment goals all shape what is appropriate.
At Cancer Healer Center, Dr Tarang Krishna and his team work with patients to clearly understand their options, including the potential role of immunotherapy, so that patients can make informed decisions at every stage of care.
Schedule a consultation to discuss your situation and receive guidance tailored to your needs.
Benefits of Immunotherapy for Cancer
Responses That Can Outlast Treatment
One of the more clinically notable findings from immunotherapy research is durability. With conventional treatments, the effect on cancer typically ends when treatment is stopped. In some patients receiving immunotherapy, the immune system continues to suppress cancer activity long after the last dose, because it has essentially been trained to do so.
This does not happen for every patient, and outcomes vary considerably across cancer types and individuals. But when durable responses occur, they are meaningful.
A Mechanism That Differs From Chemotherapy
Because immunotherapy does not target dividing cells the way chemotherapy does, it is sometimes an option for patients who cannot tolerate conventional treatment or who have stopped responding to it. For these patients, having a mechanistically different approach available matters.
Changed Outcomes in Certain Advanced Cancers
In some cancer types, particularly advanced melanoma and certain lung cancers, immunotherapy has shifted what is survivable. Survival rates that were previously very poor have improved substantially for patients whose tumours respond to these treatments.
Compatibility With Other Treatments
Immunotherapy may be used alongside:
Chemotherapy
Radiation therapy
Surgery
Targeted therapy
This flexibility allows oncologists to design treatment plans that combine approaches, rather than relying on any single method.
Dr Padmanee Sharma, a leading immunologist and oncologist at MD Anderson Cancer Center, has noted that the immune system, once properly activated, can sustain responses against cancer far beyond what any single course of treatment could achieve alone.
What Are the Side Effects of Immunotherapy?
Because immunotherapy activates the immune system, its side effects are different in character from those associated with chemotherapy. It does not damage healthy tissue directly, but it can sometimes cause the immune system to become overactive and attack normal organs. These are called immune-related adverse events.
Common side effects include:
Fatigue
Fever
Skin rash
Itching
Diarrhoea
Joint pain
Nausea
Less commonly, inflammation may affect:
Lungs
Liver
Kidneys
Thyroid gland
Intestines
The majority of these reactions can be managed if they are identified and treated. Patients undergoing immunotherapy are monitored closely during treatment, with regular blood tests and check-ups.
Immunotherapy for Cancer in India
Access to immunotherapy for cancer in India has grown substantially over the past ten years. Checkpoint inhibitor therapy and monoclonal antibody treatments are now available at most leading oncology centers in India. CAR T-cell therapy is available at select specialised institutions, and clinical trials investigating newer immunotherapy approaches are becoming more widely accessible across the country.
Immunotherapy can be more expensive than other treatments, but the gap is closing as more options enter the market. Patients should discuss expected benefits, realistic risks, and financial planning with their oncology team before beginning treatment.
| Treatment Type | Approximate Cost Range (India) |
|---|---|
| Checkpoint inhibitors (per cycle) | ₹80,000 to ₹3,00,000+ |
| Monoclonal antibodies (per cycle) | ₹50,000 to ₹2,00,000+ |
| CAR T-cell therapy | ₹30,00,000 to ₹60,00,000+ |
Final Thoughts
For much of the history of cancer treatment, the approach has been fairly consistent: locate the disease and try to destroy it with surgery, drugs, or radiation. Immunotherapy represents a genuinely different line of thinking, one that works with the body's own systems rather than around them.
It is not a universal answer and does not work the same way for every patient or cancer type. But for patients who are candidates, it has changed what is possible. And for anyone navigating a cancer diagnosis, understanding how it works is a reasonable place to start.
Consult Dr Tarang Krishna at Cancer Healer Center
If you or a loved one is working through cancer treatment decisions, Dr Tarang Krishna and the team at Cancer Healer Center can help you understand your options, including the role of immunotherapy and where supportive care fits alongside it.
The focus is on patient-centred guidance that works in coordination with conventional cancer treatment, helping patients stay informed, maintain quality of life, and approach each stage of care with clarity.
Schedule a consultation to discuss your situation and receive guidance tailored to your needs.
This article is for informational purposes only. Please consult a qualified oncologist or healthcare professional for personalised medical advice
