Chemotherapy and radiation therapy are two of the most common cancer treatments prescribed by oncologists. While both aim to destroy cancer cells, they work to do so in different ways and have distinct applications, benefits, and side effects.
Chemotherapy
What is chemotherapy?
Chemotherapy is a type of therapy that involves the use of drugs to kill cancer cells or stop them from growing and dividing. Chemotherapy can be taken orally, infused intravenously, or injected, allowing the drug to travel throughout the body.
How does chemotherapy work?
Chemotherapy works efficiently to target cancer cells dividing at a rapid rate, which is a hallmark of cancer. It can also affect healthy fast-growing cells, such as those in the hair, digestive system, and bone marrow.
When is chemotherapy used?
Chemotherapy is used to treat cancers that have spread or are present in multiple areas of the body. It’s also used to shrink tumors prior to surgery or radiation therapy. Chemotherapy can also be used as a follow up to surgery or radiation therapy to destroy any remaining cancer cells. In advanced cancers, palliative chemotherapy is used to alleviate cancer symptoms.
What are common side effects of chemotherapy?
Common side effects of chemotherapy can include:
- Hair loss
- Fatigue
- Nausea
- Vomiting
- Increased risk of infection
- Mouth sores
Radiation Therapy
What is radiation therapy?
Radiation therapy uses high-energy beams, like x-rays or protons, to target and kill cancer cells. Radiation therapy varies from chemotherapy in that it’s a localized treatment, meaning it focuses on a specific part of the body.
How does radiation therapy work?
Radiation works to damage the DNA within cancer cells, which further prevents them from growing and dividing. Over time, the damaged cells die, and the body will eliminate them naturally.
When is radiation therapy used?
Radiation therapy is often used to treat localized tumors, but it can also be used to shrink tumors prior to surgery and destroy any remaining cells following. In some instances, radiation therapy is used to relieve pain or other systems caused by cancer.
What are common side effects of radiation therapy?
Some common side effects of radiation therapy can include:
- Skin irritation or burns to the treated area
- Fatigue
- Swelling or inflammation to the treated area
- Site-specific effects, such as difficulty swallowing (if treating the throat specifically)
Key Differences Between Chemotherapy and Radiation Therapy:
- Chemotherapy is systemic, meaning it affects the whole body, whereas radiation therapy is localized, meaning it targets only a specific area.
- Chemotherapy can be delivered orally, via IV or injection, while radiation therapy is administered by using external beams or internal implants.
- Chemotherapy is best for cancers that have spread, while radiation therapy is best for cancers confined to a specific area.
- Chemotherapy is typically administered in cycles lasting weeks or months, whereas radiation therapy typically is done in daily sessions over several weeks.
- Chemotherapy drugs can have system-wide side effects, while the side effects stemming from radiation therapy and generally localized to the treated area.
Can They Be Used Together?
Yes, chemotherapy and radiation therapy are often used in tandem for certain cancers. This approach is referred to as chemoradiation, and can improve the effectiveness of each treatment, especially in the instance of cancers like head and neck, cervical or lung cancer.
Choosing the Right Treatment
The choice between chemotherapy, radiation therapy or a combination of both depends largely on the type and stage of cancer you or a loved one has been diagnosed with, the location of the tumor(s), and the patient’s overall health and treatment goals. Speak with a trusted healthcare provider for you or your loved one to understand which option is best suited for the situation at hand.