For an overview on radiation therapy, including types of radiation therapy and safety for the patient and family, read the Cancer.Net Feature: Part I: Understanding Radiation Therapy.

Why undergo radiation therapy?

For some cancer types, such as rectal and larynx cancers, radiation therapy alone can often provide a successful treatment. Other types of cancer respond best to combination treatment approaches, including surgery, chemotherapy, and immunotherapy. Research indicates that for breast and lung cancers, radiation therapy can significantly reduce the chances of cancer recurrence when used along with other forms of treatment. In addition, radiation therapy can be used as palliative care to relieve pain because of its ability to quickly reduce the size of the tumor.

The radiation therapy team

A team of highly trained medical professionals works together to provide the best possible care during radiation therapy. This team is led by a radiation oncologist who specializes in using radiation to treat cancer.

Radiation oncologist. A radiation oncologist is a doctor who oversees your radiation therapy treatments and works closely with other members of the radiation therapy team to develop your personal treatment plan.

Radiation oncology nurse. The radiation oncology nurse answers questions, provides information about the treatments and both the current and possible side effects, makes assessments about your current health status, and offers emotional assistance to you and your family.

Medical radiation physicist. As an expert in ensuring the proper functioning of the sophisticated radiation equipment, a medical radiation physicist provides the appropriate dose for each patient and helps the radiation oncologist design the often complex treatment plans.

Dosimetrist. Supervised by the medical radiation physicist, a dosimetrist helps the radiation oncologist plan the most effective treatments.

Radiation therapist or radiation therapy technologist. Primarily responsible for maintaining and operating the treatment machines and administering your daily treatments.

Other health-care professionals. Specialists work to meet all of your physical and psychological needs during treatment, and can include:

• Social workers
  
  
• Nutritionists or dietitians
  
  
• Physical therapists
  
  
• Dentists

Before treatment

Consultation and informed consent. Before treatment, you will meet with a radiation oncologist to evaluate whether radiation therapy is necessary. The doctor reviews your record and performs a physical examination, then discusses with you the potential risks and benefits of radiation therapy. This is also your opportunity to ask the doctor questions. Should you choose to receive radiation therapy, you will be asked to give written permission and have the appropriate tests to plan the treatment and assess their results. The informed consent form confirms that you have received information about treatment options and that you are willing to undergo radiation therapy. Your signed consent also means that you understand there is no guarantee that the treatment will achieve the intended results.

Simulation and treatment planning. Your first session in the radiation therapy department does not involve an actual treatment. This initial visit is called a simulation. You will have a scan or x-rays performed in the treatment position, and this provides the medical team with the opportunity to adjust the radiation beam to your body and focus it directly at your tumor. Because the radiation beam must be aimed precisely each and every time treatment is given, you will be measured and marked with bright temporary paint or a set of small permanent tattoos.

Special blocks or shields may be made for you. These function to position you correctly and to keep the radiation from damaging normal tissues surrounding the tumor.

Following the simulation, your radiation therapy team reviews your information and designs a treatment plan. Frequently, use of sophisticated computer software helps develop this plan. Your doctor then writes a prescription outlining the course of your radiation treatment.

During treatment

The types of radiation therapy you may receive are discussed in the Part I: Understanding Radiation Therapy.

External-beam radiation therapy. Given as a series of outpatient treatments, external-beam radiation treatments are quick, painless, and frequent. Treatments are usually scheduled five times a week, Monday through Friday, and continue for three to 10 weeks. Only about 30 minutes are spent at the hospital each day and side effects, especially initially, are minimal.

Although the radiation beam and your body position are adjusted so the radiation targets only the tumor, radiation affects some of the normal tissues surrounding the tumor. The two-day pause in treatments each week allows normal cells to repair the radiation damage.

Internal radiation therapy (also called brachytherapy). Both temporary and permanent placement of radioactive sources in the body can require anesthesia and a brief hospital stay. If you have a permanent implant, the radioactive sources can give off radiation for a short period of time after receiving the implant. You will be under a few restrictions to protect other people from radiation exposure. Internal radiation therapy may be repeated over a number of days or weeks. Most patients experience little discomfort during their treatment, but some people request medication to overcome weakness or nausea from the anesthesia.

Weekly progress reports. Your radiation oncologist evaluates your progress weekly and may adjust your treatment plan accordingly. In addition, your treatment team makes use of special x-rays taken weekly, called beam films, to assess the aim of the treatment beams. Again, precise targeting of the tumor is crucial for optimal radiation therapy.

Personal care. Many people experience fatigue, skin sensitivity at the site of radiation exposure, and emotional distress during radiation therapy. The best way to care for yourself is to plan for extra rest, stay on a balanced, nutritious diet, treat skin with lotions approved by your health-care team, minimize sun exposure, and seek emotional support.

After treatment

Your radiation oncologist will request follow-up appointments to ensure normal recovery and to evaluate your health status. It is important to remember that the effects of your radiation therapy cannot be assessed immediately following the treatment period, as your body will continue to respond to the effects of the radiation for a period of time afterward. As you heal, the need for follow-up appointments will decrease.

Side effects of radiation therapy

Side effects vary from patient to patient and depend on the treatment dose, the part of your body treated, and your general health. Many patients have no side effects at all. If side effects do occur, they usually begin by the second or third week of treatment, and may last for several weeks after the final radiation treatment. Examples of some side effects include: nausea, fatigue, hair loss at the radiation therapy site, low blood count, fever/chills, and skin irritation. Late side effects, such as infections, organ malfunctions, infertility issues, and secondary cancers, may take months or even years to develop. Unfortunately, these later effects may be longer lasting or permanent.

The most frequent side effect reported by patients is fatigue. Because anemia (low red blood cell count), stress, poor diet, and depression contribute to cancer-related fatigue, health-care professionals use multiple approaches to control this side effect. For more information on cancer-related fatigue, please read the Cancer.Net Feature: Coping With Cancer-Related Fatigue.

A significant concern of patients is whether radiation therapy will cause another cancer later in life. The risk of developing a secondary cancer because of radiation therapy is low and that risk is generally outweighed by the benefit of treating the primary, existing cancer. However, radiation therapy to certain parts of the body can cause secondary cancers some years later. It is recommended that patients discuss this with your radiation oncologist. The risk of having difficulties conceiving exists only if the ovaries or testicles have received radiation treatment and is minimized by reducing unnecessary exposure of the body to radiation outside the cancer site itself.

Side effects occur that are specific to the area of the body where radiation therapy is focused. An additional feature article on Cancer.Net will be posted this fall that will discuss side effects of radiation therapy of particular cancers.

Just as every patient is different, so are the side effects he or she experiences. Keep your medical treatment team informed of your symptoms and ask for help when needed. Take advantage of patient information booklets available through your doctor.

More Information

Part I: Understanding Radiation Therapy

Part III: Side Effects of Radiation Therapy

Frequently Asked Questions About Radiation Therapy

Additional resources

National Cancer Institute (NCI): Radiation Therapy for Cancer: Questions and Answers

NCI: Radiation Therapy and You: A Guide to Self-Help During Cancer Treatment

The American Society for Therapeutic Radiology and Oncology (ASTRO) RT Answers: Radiation Therapy for Cancer

RT Answers: About the Radiation Oncology Treatment Team

Medline Plus: Radiation Therapy Introduction (tutorial)

American Cancer Society (ACS): Radiation Therapy Principles

ACS: Questions About Radiation Therapy

MayoClinic.com: Radiation therapy: Using high-powered x-rays to kill cancer cells

Kids Health: Radiation Therapy

Last Updated: July 25, 2005