Is cancer immunotherapy the same as chemotherapy?

No, cancer immunotherapy is not the same as chemotherapy. Although both are types of cancer treatment, they work in completely different ways to combat cancer cells [1].

What is immunotherapy?

Immunotherapy is a type of biological therapy that leverages the body's immune system to fight cancer. The immune system naturally works to detect and destroy abnormal cells, including cancer cells. However, cancer cells can evolve in ways that allow them to evade detection and destruction by the immune system. Immunotherapy comes into play here to enhance the immune system's ability to recognize and attack these cancer cells more effectively [1].

Immunotherapy can work in several ways, including:

• Immune checkpoint inhibitors: These are drugs that block natural checkpoints in the immune system that prevent immune responses from becoming too strong. By blocking these checkpoints, these drugs allow immune cells to respond more strongly to cancer [1].
• T-cell transfer therapy: This treatment boosts the natural ability of T-cells to fight cancer. Immune cells are taken from the tumor, and the most active cells against cancer are selected or modified in the lab to better attack cancer cells, then expanded and returned to the body [1].
• Monoclonal antibodies: These are immune system proteins created in the laboratory to bind to specific targets on cancer cells. Some mark cancer cells so they are easier to see and destroy by the immune system [1].
• Therapeutic vaccines: These vaccines work to enhance the immune system's response to cancer cells [1].

How is it different from chemotherapy?

While immunotherapy focuses on boosting the body's natural defenses, chemotherapy uses powerful chemicals to kill fast-growing cells in the body, including cancer cells. This means that chemotherapy can also affect healthy, fast-growing cells, leading to different side effects [1]. In contrast, side effects of immunotherapy may occur when the immune system, activated to fight cancer, attacks healthy cells and tissues in the body [1].

Is immunotherapy used for all types of cancer?

Immunotherapy is not used for all types of cancer, and response to treatment varies. Although immunotherapy drugs have been approved for many types of cancer, they are not as widely used as surgery, chemotherapy, or radiation therapy [1]. Researchers are conducting clinical trials to see if immunotherapy works for other types of cancer [2].

What are the side effects of immunotherapy?

Immunotherapy can cause side effects, many of which occur when the immune system, activated to fight cancer, also attacks healthy cells and tissues in the body [1]. Common side effects include skin reactions at the injection site if administered intravenously, flu-like symptoms, and, in rare cases, severe reactions [2].

Next Steps

If you are receiving immunotherapy, your healthcare provider will monitor your treatment closely [2]. It is important to ask your doctor about potential side effects, how to manage them, which medications to avoid, and when to contact them about any concerning symptoms [3]. You may need to visit your doctor frequently for physical exams, blood tests, and various types of scans to monitor tumor size and changes in blood test results [1].

For deeper information on how immunotherapy works, you can visit Cancer Immunotherapy: How does the immune system fight cancer? (Arabic)

Medical references

• Immunotherapy to Treat Cancer
• Cancer Immunotherapy
• Immunotherapy: questions to ask your doctor