Targeted Therapy vs. Immunotherapy: Key Differences & Benefits

Targeted therapy and immunotherapy are both used to treat cancer, but they work in different ways. Targeted therapy blocks specific molecules that help cancer grow, while immunotherapy helps the immune system fight cancer on its own.

The choice between these treatments depends on the type of cancer and how well it responds. Some cancers are treated better with targeted therapy, while others respond more to immunotherapy. In some cases, both treatments may be used together for better results.

This article explains how targeted therapy and immunotherapy work, their key differences, and what patients expect from each treatment.

How does Targeted Therapy Work?

Targeted therapy blocks specific molecules that cancer cells need to grow and spread. This makes it different from chemotherapy, which attacks all fast-growing cells, including healthy ones.

• Blocks Cancer Growth Signals: Some cancer cells grow because of abnormal signals in their genes. Targeted therapy blocks these signals, stopping the cancer from growing.
• Attacks Specific Cancer Cells: Unlike chemotherapy, which affects healthy cells too, targeted therapy mainly attacks cancer cells. This lowers the risk of side effects compared to traditional treatments.
• Types of Targeted Therapy: Some drugs stop the blood supply that feeds tumours, while others block proteins that help cancer grow. Different drugs work for various types of cancer.
• Used in Certain Cancers: Targeted therapy is most effective in cancers where specific gene mutations are known, such as breast cancer, lung cancer, and some blood cancers.

Targeted therapy is designed to attack cancer cells while causing less harm to normal cells, making it a more precise treatment option.

How Immunotherapy Works?

Immunotherapy helps the body’s immune system recognise and destroy cancer cells. Instead of attacking cancer directly, it strengthens the body’s natural defences.

• Boosts the Immune System: Cancer cells often hide from the immune system. Immunotherapy helps immune cells find and destroy these cancer cells.
• Different Types of Immunotherapy: There are various forms, including checkpoint inhibitors, monoclonal antibodies, and CAR-T cell therapy. Each type works in a different way to improve the immune response.
• Long-Term Effects: Some types of immunotherapy train the immune system to remember cancer cells, reducing the risk of cancer returning.
• Works for Certain Cancers: Immunotherapy is commonly used for cancers like melanoma, lung cancer, and some blood cancers. It is beneficial in cancers that do not respond well to chemotherapy.

Immunotherapy works with the body’s defence system, providing a natural way to fight cancer over time.

Key Differences Between Targeted Therapy and Immunotherapy

While both treatments aim to stop cancer, they do so in different ways. Here are some key differences:

• How They Work: Targeted therapy blocks cancer’s growth signals, while immunotherapy helps the immune system recognise and attack cancer cells.
• Treatment Focus: Targeted therapy directly affects cancer cells, while immunotherapy strengthens the body’s natural defences against cancer.
• Side Effects: Targeted therapy may cause skin rashes, diarrhoea, or liver problems. Immunotherapy side effects are usually related to immune reactions like inflammation or flu-like symptoms.
• Effectiveness: Some cancers respond better to targeted therapy, while others are more suited for immunotherapy. The choice depends on the type of cancer and individual response to treatment.

Side Effects of Targeted Therapy and Immunotherapy

Both treatments have side effects, but they affect the body in different ways.

• Targeted Therapy Side Effects:
  • Skin problems like rashes, dryness, or itching are common.
  • Diarrhoea can occur due to the effect on digestive cells.
  • Liver issues may develop, requiring regular blood tests to monitor liver function.
  • Fatigue and weakness can happen over time but vary from person to person.
• Immunotherapy Side Effects:
  • Flu-like symptoms such as fever, chills, and body aches are common.
  • Inflammation in organs like the lungs, liver, or intestines may occur rarely.
  • Skin reactions, including redness and rashes, can develop.
  • Fatigue is common but may be less severe than chemotherapy-related fatigue.

Doctors monitor patients closely to manage these side effects and adjust treatment.

When is Targeted Therapy Recommended?

Targeted therapy is used in cases where specific genetic mutations drive cancer. It is recommended in the following situations:

• For Cancers with Known Mutations: Some cancers, like breast cancer and lung cancer, have specific mutations that targeted therapy can block.
• As a Primary Treatment: In some cases, targeted therapy is the primary treatment, especially when surgery or chemotherapy is not an option.
• In Combination with Other Treatments: Targeted therapy is sometimes used alongside chemotherapy, radiation, or immunotherapy to improve results.
• Advanced or Metastatic Cancer: It is commonly used to spread cancers and can slow down cancer growth.

When is Immunotherapy Recommended?

Immunotherapy is often used when cancer is not responding to traditional treatments. It is recommended in the following cases:

• For Certain Cancer Types: Immunotherapy is commonly used for lung cancer, melanoma, bladder cancer, and some blood cancers.
• When Other Treatments Do Not Work: Immunotherapy may be an option if chemotherapy or radiation therapy is ineffective.
• For Long-Term Cancer Control: Some types of immunotherapy help the immune system fight cancer even after treatment stops.
• As a Targeted Approach: Immunotherapy can be more focused than chemotherapy, making it useful for specific cancers with immune-related responses.

Frequently Asked Questions