Radiation Therapy for Cancer

Radiation therapy, also known as radiotherapy, is a common and effective cancer treatment that uses high-energy radiation to kill cancer cells and shrink tumors. It's a localized treatment, meaning it targets a specific part of the body, which helps to minimize damage to healthy tissues.

How It Works

Radiation therapy works by damaging the DNA within cancer cells. DNA is the genetic material that controls how cells grow and divide. When the DNA is damaged, the cancer cells can no longer grow and multiply, and they eventually die. While healthy cells can also be affected by radiation, they are generally better at repairing the damage than cancer cells. This is a key principle behind the effectiveness of radiation therapy.

Treatment is carefully planned to deliver the highest possible dose of radiation to the cancer while sparing as much healthy tissue as possible. This is achieved through various advanced techniques and technologies.

Types of Radiation Therapy

There are two main types of radiation therapy for cancer:

1. External Beam Radiation Therapy (EBRT): This is the most common type of radiation therapy. A large machine, called a linear accelerator, is used to direct high-energy beams of radiation from outside the body to the tumor. The machine moves around the patient, delivering precise doses of radiation from multiple angles to target the cancer while minimizing exposure to surrounding healthy organs. Treatment sessions are typically short, painless, and performed on an outpatient basis over several weeks.

2. Internal Radiation Therapy (Brachytherapy): This type of therapy involves placing a radioactive source directly inside the body, either in or near the tumor. The radiation source can be in the form of seeds, wires, or pellets. Brachytherapy delivers a high dose of radiation to a very small area, which is beneficial for certain cancers like those of the cervix, prostate, breast, and some head and neck cancers. The sources can be left in place permanently (where they lose their radioactivity over time) or temporarily for a set period.

Uses in Cancer Treatment

Radiation therapy can be used at various stages of cancer treatment:

• Primary Treatment: In some cases, radiation is used as the sole treatment to cure cancer, especially for certain early-stage cancers like prostate, skin, and head and neck cancers.

• Adjuvant Therapy: Radiation is often used after surgery to kill any remaining cancer cells that may have been left behind and to reduce the risk of the cancer returning.

• Neoadjuvant Therapy: Radiation can be given before surgery to shrink a tumor, making it easier to remove completely.

• Palliative Care: For advanced cancers, radiation therapy can be used to relieve symptoms, such as pain, bleeding, or breathing difficulties, to improve a patient's quality of life.

• Combined Therapy: Radiation is frequently used in combination with other treatments, such as chemotherapy or immunotherapy, to enhance their effectiveness.

Side Effects

Side effects of radiation therapy depend heavily on the area of the body being treated and the dose of radiation used. The effects are localized to the treatment area and can be temporary or long-term. Common side effects include:

• Fatigue: This is one of the most common side effects and can be caused by the body's use of energy to heal and repair itself.

• Skin Changes: The skin in the treated area may become red, dry, itchy, or swollen, similar to a sunburn.

• Hair Loss: Hair loss only occurs in the area where the radiation is delivered.

• Localized Side Effects: Other side effects are specific to the treatment area, such as a sore throat with head and neck radiation, or nausea and diarrhea with abdominal or pelvic radiation.

Many of these side effects are temporary and can be managed with proper care. A patient's healthcare team will provide guidance on managing symptoms and caring for the treated area.