The treatment of cancer and other diseases with penetrating beams of high-energy waves, or streams of particles, delivered via machines or radioactive substances.
Radiation therapy works by damaging cancer cells that, by nature, divide and grow more quickly than normal cells. Once damaged, the cancer cells are unable to grow. Although some normal cells may be damaged in the process, these normal cells are able to repair themselves and function properly.
There are two main types of radiation therapy:
- External - radiation is delivered by a machine from outside the body
- Internal - radioactive materials are placed in the body near the cancer cells; also called implant radiation or brachytherapy
In certain cases, some doctors may recommend a combination of internal and external radiation. Radiation is often used in conjunction with other types of treatment, such as surgery, chemotherapy, and immunotherapy (the stimulation of the immune system to fight infection).
PARTS OF THE BODY INVOLVED
This depends on the type of cancer being treated
REASONS FOR PROCEDURE
- To control the growth or spread of cancer
- To cure disease by completely eliminating growth
- To alleviate or reduce the symptoms of pain, this is called palliative radiation
Radiation therapy is commonly used to treat the following types of cancer:
- Localized solid tumors (e.g., cancers of the skin, neck, tongue, larynx, brain, breast, prostate, lung, anus, rectum, bone, bladder, ovary, uterus, or cervix)
RISK FACTORS FOR COMPLICATIONS DURING THE PROCEDURE
Previous radiation therapy
A woman who is pregnant or could possibly be pregnant should avoid exposure to radiation to prevent harm to the developing fetus.
WHAT TO EXPECT
Prior to Procedure -You will go through a process called simulation. This process takes between 30 minutes and 2 hours. During simulation, you will:
- Lie on an exam table while a radiation therapist uses an x-ray machine to define the exact place(s) where radiation will be directed. The therapist may mark the exact radiation area with colored ink. You will proably also have a small tatoo (or several) placed on your skin as a permanent mark to help with the aiming of the radiaiton beam.
- Depending on the type of treatment required, you may also undergo:
- CT scan – a type of x-ray that uses a computer to make pictures of the inside of the body
- Measurement for immobilization devices to help you stay still during treatment
During Procedure – Jewelry may need to be removed, and you may be asked to change into a hospital gown
Anesthesia - None
Description of the Procedure - The radiation therapist positions you on the treatment table or chair. Then the therapist leaves the room and enters a control room, where he or she controls the movements of the radiation machine (called a linear accelerator) to deliver radiation to the predetermined areas on your body. The most common sources of the radiation are x-rays, electron beams, and cobalt-60 gamma rays.
You will need to remain extremely still during the treatment, which lasts from 1 – 5 minutes. The therapist can see you through a television screen, and you can talk with the therapist if you feel uncomfortable or sick.
After Procedure -You are free to leave and resume your normal activities. You are not radioactive after your treatment and you are not a threat to anyone else around you, in terms of radiation exposure.
How Long Will It Take? The actual treatment takes only a few minutes, but you should allow at least 30 minutes for each session. Most treatments last from 2 to 8 weeks, and are given once a day, five days per week. In some cases you may be treated twice daily or only three times a week, and this will depend on various factors. Discuss the logistics of the actual scheduling with your radiation oncologist.
Will It Hurt? No
External radiation does not cause your body to become radioactive. You may, however, experience side effects. These effects will vary depending on the type and location of cancer treatment. Common side effects of radiation include, but are not limited, to:
- Skin changes (redness, irritation)
- Reduced white blood cell count
- Hair loss
- Dryness or itchiness of the breasts
- Breast or nipple soreness
- Fluid buildup
- Tanning in irradiated area
Mouth, Stomach, or Intestine
- Appetite loss
- Nausea, vomiting, or diarrhea
- Mouth ulcers
- Difficulty swallowing
- Bladder irritation
- Vaginal itching, burning, dryness, or menstrual cessation
- Reduction of sexual desire
- Possible loss of fertility
Tell your doctor if you experience these side effects, so that steps can be taken to reduce your discomfort. Many side effects can be controlled with medication or diet. If the side effects are dramatic, your doctor may alter or delay the course of your treatment. After treatment, most side effects will gradually diminish and disappear.
Average Hospital Stay – None; external radiation is typically done on an outpatient basis.
Postoperative Care - During treatment, your doctor will want to see you at least once a week. You may have routine blood tests to check the levels of red blood cells, white blood cells, and platelets to assess the effect of radiation on these blood cells. After treatment is completed, you will be scheduled for regular visits to monitor healing, and check for signs of recurrent disease. Follow-up care will vary for each patient, and may include further testing, medication, or rehabilitative treatment.
Prior to Procedure - You will be given general or local anesthesia so that you will not feel any pain when the doctor places the holder for the radioactive material in your body.
During procedure -In many hospitals, the radioactive material is placed in its holder or applicator after you return to your room so that other patients, staff, and visitors are not exposed to radiation.
Implants may be removed after a short time or left in place permanently. If they are to be left in place, the radioactive substance used will lose radiation quickly and become non-radioactive in a short time.
Anesthesia -Local or General
Description of the Procedure - The radiation source is placed inside the body directly on or near the affected area. This method provides higher doses of radiation in a shorter time than external radiation. The radioactive sources (such as cesium, iridium, palladium, or iodine) are usually in the form of wires, seeds, or rods. This type of treatment is most commonly used for cancers of the head and neck, breast, uterus, thyroid, cervix, and prostate. The two main types of internal radiation are:
- Interstitial radiation:
Rods, ribbons, or wires are placed inside the affected tissue on a temporary or permanent basis.
- Intracavitary radiation:
A container of radioactive material is placed inside a body cavity, such as the uterus, vagina, or windpipe. This is always temporary.
After procedure -You will return to a hospital room while the implant is in place. While the radiation is implanted, you will need to follow these precautions to prevent transmitting radiation to others:
- Limited visitation:
Many hospitals do not allow children under the age of 18 or pregnant women to visit a patient undergoing implant radiation until the implant is removed. If visitors are allowed, they will need to sit at least 6 feet from the bed, and their visits will be limited to a short time (10-30 minutes). A shield may be placed beside the bed to protect visitors and staff from radiation exposure.
- Limited contact with the staff:
Although the staff will be available to you at all times, be aware that they may speak to you from the doorway, and/or come and go very quickly to avoid excessive radiation exposure.
How Long Will it Take? This depends on the type of cancer to be treated and the method of internal radiation used
Will it Hurt? Anesthesia prevents pain during the procedure
Possible Complications - You may experience side effects, which are described above under "Possible Complications" of the "External Radiation" section.
Average Hospital Stay – You will stay in the hospital until the implant is removed, or in the case of a permanent implant, when the radioactivity has decreased. High-dosage implants are usually removed within a matter of minutes, but low-dosage implants may remain in for a few days. Permanent implants lose their radioactivity within a few days.
Postoperative Care – During treatment, your doctor will want to see you at least once a week. You may have routine blood tests to check the levels of red blood cells, white blood cells, and platelets to assess the effect of radiation on these blood cells. After treatment is completed, you will be scheduled for regular visits to monitor healing, and check for signs of recurrent disease. Follow up care will vary for each patient, and may include further testing, medication, or rehabilitative treatment.
Ideally, radiation therapy will result in shrinkage or complete elimination of the cancerous or diseased area.
CALL YOUR DOCTOR IF ANY OF THE FOLLOWING OCCURS
- Signs of infection, including fever and chills
- Cough, shortness of breath, chest pain, or severe nausea or vomiting
- Pain that doesn't go away, especially if it's always in the same place
- New or unusual lumps, bumps, or swelling
- Nausea, vomiting, diarrhea, or loss of appetite
- Unexplained weight loss
- Fever or cough that doesn't go away
- Unusual rashes, bruises, or bleeding
- Any symptoms that you are concerned about
- Any other warning signs mentioned by your doctor or nurse
National Cancer Institute
Oncolink: University of Pennsylvania Cancer Center