Difference Between Chemotherapy and Immunotherapy

Cancer treatment have developed rapidly over the past few years. Nowadays, there are multiple treatment options available for patients. Most of these treatment options vary in different kinds and stages of cancer but two treatment options have gained a lot of coverage. One option is the traditional approach ofr treating cancer- chemotherapy which has been used since decades. Another option is an advanced treatment approach- immunoterhapy. 

Understanding how these treatments differ is important for making informed decisions about care. In this article, we explain chemotherapy and immunotherapy in simple terms, how they work, their side effects, and when they are used.

What Is Chemotherapy?

Chemotherapy is one of the oldest cancer treatments. It involves the use of drugs to kill fast-growing cells, including cancer cells. Since cancer cells divide rapidly, chemotherapy targets them to slow their growth or eliminate them completely.

• How It Works: Chemotherapy drugs circulate through the bloodstream and attack cells that divide quickly. Because cancer cells multiply at an abnormal rate, chemotherapy helps control their spread. However, it also affects healthy cells that grow quickly, such as those in the hair, digestive tract, and bone marrow.
• Common Side Effects: Since chemotherapy affects healthy cells, patients may experience various side effects. These can range from hair loss, feeling nauseous frequently, experiencing fatigue and a weakened immunity.
• How It Is Given: Chemotherapy can be administered in different ways, including intravenous injections, oral pills, or direct placement into the affected area.
• Purpose of Treatment: It can be used before surgery to shrink tumors, after surgery to eliminate remaining cancer cells, or as the main treatment for cancers that cannot be removed surgically.

What Is Immunotherapy?

Immunotherapy is one of the advanced treatment option that uses the body’s natural immune system to fight cancer. Instead of attacking cancer cells directly, immunotherapy strengthens the immune response so that the body can identify and destroy cancer more effectively.

• How It Works: Cancer cells can sometimes hide from the immune system. Immunotherapy helps by either boosting the immune response or making cancer cells more visible to the immune system.
• Types of Immunotherapy: There are different forms of immunotherapy, including:
  • Checkpoint Inhibitors: These drugs block proteins that prevent the immune system from attacking cancer cells.
  • Cancer Vaccines: These help train the immune system to recognize cancer cells as a threat.
  • T-Cell Therapy: Immune cells are modified in a lab to fight cancer and then returned to the patient’s body.
• Common Side Effects: Because immunotherapy boosts the immune system, it can sometimes cause it to attack healthy tissues. Side effects may include skin rashes, flu-like symptoms, and inflammation in different organs.
• How It Is Given: Immunotherapy is usually given through an IV infusion over several sessions. The duration of treatment varies depending on how well the immune system responds.

Key Differences Between Chemotherapy and Immunotherapy

While both chemotherapy and immunotherapy are used to treat cancer, they have major differences in how they work and how they affect the body.

• Method of Action:
  • Chemotherapy kills rapidly dividing cells, both cancerous and healthy.
  • Immunotherapy strengthens the immune system to recognize and destroy cancer cells.
• Side Effects:
  • Chemotherapy causes side effects such as hair loss, nausea, and fatigue due to its impact on healthy cells.
  • Immunotherapy may cause immune-related side effects, including skin problems, fever, and inflammation.
• Treatment Duration:
  • Chemotherapy is given in cycles, with rest periods in between to allow recovery.
  • Immunotherapy often takes longer to show results, but its effects may last even after treatment stops.
• Effectiveness in Different Cancers:
  • Chemotherapy is widely used for many cancer types and is often the first line of treatment.
  • Immunotherapy is more effective for cancers like melanoma and lung cancer, especially when other treatments have not worked.

When Is Each Treatment Used?

Doctors decide whether chemotherapy or immunotherapy is the best option based on factors like the type of cancer, its stage, and how the body responds to treatment.

• Chemotherapy is used when:
  • The cancer is fast-growing and needs to be controlled quickly.
  • The goal is to shrink a tumor before surgery.
  • Cancer has spread to multiple areas and needs to be treated systemically.
• Immunotherapy is used when:
  • The cancer is not responding to chemotherapy.
  • The immune system can be trained to fight the cancer effectively.
  • The cancer is known to respond well to immunotherapy, such as melanoma or certain lung cancers.

Expected Outcomes and Follow-Up

Both treatments require regular follow-ups to monitor progress and manage side effects.

• Chemotherapy Outcomes:
  • Some patients respond well, with tumors shrinking or disappearing completely.
  • Others may need ongoing treatment to keep the cancer under control.
  • Regular blood tests and scans are used to track progress.
• Immunotherapy Outcomes:
  • Immunotherapy may take longer to work, but when successful, the immune system continues fighting cancer even after treatment ends.
  • Some patients experience long-term remission, while others may need combination treatments.

Conclusion

Chemotherapy and immunotherapy are both important cancer treatments, but they work in different ways. Chemotherapy directly targets cancer cells, while immunotherapy helps the body’s immune system fight cancer more effectively.

Regular monitoring and early detection are key to making these treatments more effective. If you or a loved one is considering cancer treatment, discussing these options with a doctor can help determine the best approach.

Frequently Asked Questions