Immunotherapy is a form of cancer treatment that uses immune-boosting medicines to help the body detect and destroy cancer cells. It improves the ability of T-cells (a type of white blood cell) to recognize cancer as a threat.
Why Is Immunotherapy Used?
Doctors recommend immunotherapy when:
- Cancer does not respond to chemotherapy
- Cancer has spread (metastasized)
- Patients cannot tolerate strong chemotherapy drugs
- Improves long-term survival in many cancers
How Does Immunotherapy Work?
Cancer cells hide from the immune system by releasing proteins that deactivate immune cells. Immunotherapy blocks these signals, allowing the immune system to:
- Detect cancer
- Trigger an immune attack
- Kill cancer cells
- Prevent cancer from growing or spreading
Types of Immunotherapy
- Immune Checkpoint Inhibitors: Block proteins (PD-1, PD-L1, CTLA-4) that stop immune cells from attacking cancer. Example: Pembrolizumab, Nivolumab, Atezolizumab
- CAR T-Cell Therapy: Doctors modify a patient's T-cells in the lab to make them stronger cancer fighters. Highly effective for blood cancers
- Monoclonal Antibodies: Lab-made proteins that target cancer cells directly or mark them for immune attack
- Cancer Vaccines: Train the immune system to recognize and destroy cancer-causing cells. Example: HPV vaccine prevents cervical cancer
- Cytokines: Proteins like Interleukin-2 and Interferons help boost overall immune activity
- Oncolytic Virus Therapy: Modified viruses infect and kill cancer cells, triggering an immune response
Which Cancers Can Immunotherapy Treat?
Immunotherapy is used for several cancers, including:
- Lung cancer
- Melanoma (skin cancer)
- Kidney cancer
- Liver cancer
- Bladder cancer
- Lymphoma and leukemia
- Head and neck cancer
- Cervical cancer
- Colorectal cancer
- Prostate cancer
How Is Immunotherapy Given?
- Intravenous (IV): Most common; given through a drip in a hospital
- Oral: Some immunotherapy drugs are available as pills
- Topical: Creams used for early-stage skin cancers
- Intravesical: Drug delivered directly into the bladder for bladder cancer
Sessions may occur every 2–4 weeks depending on the treatment plan.
Benefits of Immunotherapy
- Boosts the natural immune system
- Fewer side effects than chemotherapy in many cases
- Works even when cancer spreads
- Long-lasting results (immune memory)
- Can be combined with chemo or targeted therapy
- Improves survival in many cancers
Side Effects of Immunotherapy
Immunotherapy stimulates the immune system, which may cause inflammation in organs. Common side effects include:
- Fatigue
- Skin rash or itching
- Fever or chills
- Diarrhea
- Body aches
- Nausea
- Cough or breathing difficulty
- Thyroid imbalance
Serious but rare side effects:
- Lung inflammation (pneumonitis)
- Liver inflammation (hepatitis)
- Colitis
- Heart inflammation
- Severe hormonal changes
How Long Does Immunotherapy Last?
Treatment duration depends on cancer type and response, usually 6 months to 2 years. Some patients experience long-term remission even after stopping treatment.
Who Is Eligible for Immunotherapy?
You may be eligible if:
- Your cancer expresses PD-L1 or specific genetic markers
- You have advanced or metastatic cancer
- Chemotherapy is not effective
- You are medically fit for immune-boosting drugs
How Effective Is Immunotherapy?
Effectiveness varies, but many cancers show remarkable response. Some patients achieve tumor shrinkage, complete remission, or long-term cancer control. Certain cancers like melanoma and lung cancer respond especially well.
Precautions During Immunotherapy
- Report fever or cough immediately
- Avoid smoking and alcohol
- Stay away from infections
- Maintain a healthy diet
- Regular blood tests
- Keep track of thyroid and liver function
