Radiation and chemotherapy are two main forms of cancer treatment that differ in their approach and mechanism of action. Both methods can be used either alone or in combination with other treatments such as surgery to fight cancer cells, slow or stop the growth of tumors, and relieve symptoms.
Radiation therapy uses high-energy radiation, such as X-rays or gamma rays, to destroy cancer cells or inhibit their growth. The radiation damages the DNA of the cancer cells, which means they can no longer grow or divide. Radiation therapy can be delivered externally (from outside the body) using a linear accelerator or internally (inside the body, known as brachytherapy), where radioactive sources are near the tumor to be placed.
May include skin reactions in the irradiated area, fatigue, changes in blood counts and, depending on the area of treatment, specific organ side effects such as dry mouth when irradiated in the head and neck area.
Chemotherapy involves the use of drugs (chemotherapeutics) to kill cancer cells or stop them from growing. These drugs can be administered orally, intravenously, or through other routes and work by targeting rapidly dividing cells. Because chemotherapy works throughout the body, it can reach cancer cells almost anywhere.
Include nausea and vomiting, hair loss, oral thrush, fatigue, increased risk of infection due to decreased leukocyte count, and specific organ toxicities depending on the chemotherapy agent used.
The choice between radiation therapy and chemotherapy, or the decision to combine both, depends on several factors, including the type and stage of the cancer, the patient's overall health, the goals of the treatment, and the potential side effects. Treatment planning is individualized and based on a careful assessment by a multidisciplinary team of cancer specialists.
In many cases, a combination of radiation and chemotherapy, along with other treatment approaches such as targeted therapy or immunotherapy, is the most effective strategy for fighting cancer.