Treating Cancer with Radiation

Using radiation therapy to treat cancer

Radiation plays an important role in treating many types of cancers. It is also used to alleviate some of the symptoms of advanced cancer. There are several types of radiation. The use of radiation and which type varies by cancer, stage and situation.

What is radiation therapy?

Radiation is a type of energy. Radiation therapy (also known as radiotherapy) uses high concentrations of radiation to kill cells, especially those that grow quickly. Many cancers grow and divide quickly and abnormally, making them good targets for radiation therapy. Normal cells, such as skin, hair, and the cells that line the intestinal tract also grow rapidly, and radiation therapy can damage these too. This can lead to the side effects that people on  radiation therapy experience.

Types of radiation therapy

The different types of radiation therapy vary by how they are given and when they are used:

• External-beam radiation therapy (EBRT) uses a machine that aims radiation beams at the tumor to kill cancer cells. This treatment can be used to treat localized cancers or help relieve symptoms if the cancer has spread. Before treatment, the radiation oncologist maps out the areas of the body where the radiation will be focused. Before radiation treatment begins, the area being treated may be marked with tiny tattoos to help guide where the machine will focus the beam. External-beam radiation is used to treat a variety of cancer types including breast, prostate and rectal cancers.  
• Brachytherapy is a type of internal radiation. It involves surgery to implant radioactive seeds to kill the cancer. Brachytherapy is used most frequently to treat prostate and breast cancer after surgery. Because the radioactive material is implanted in their body, people undergoing brachytherapy, must take special precautions to minimize exposing other people to radiation. Brachytherapy is used to treat breast, endometrial, prostate and other types of cancer. 
• Radiopharmaceutical drugs are a type of radiation that is delivered into the body by injection or oral medication. Examples include radioligand therapy used to treat prostate cancer, and radioactive iodine used to treat thyroid cancer. 
  • Radioligands are a type of targeted radiation that are injected directly into the body. These drugs are made up of two components: 1) a targeting agent that can find and attach to cancer cells and 2) a radioactive chemical that kills cancer cells once they are exposed. Currently, radioligand therapies have been approved for use in prostate cancer, lymphoma, and a type of blood cancer known as a neuroendocrine tumor. 
• Thyroid cells take up iodine to make thyroid hormones. Radioactive iodine (also known as radio-iodine therapy or I-131 therapy) is given as a capsule taken orally as a type of targeted therapy to treat thyroid cancer while sparing other organs. 

You can read more about the role of radiation for different cancers in our section on Treatment by Cancer Type. Like all cancer treatments, radiation can have side effects. Read below for more information on side effects of radiation.

When is radiation therapy given?

After a diagnosis of cancer, radiation therapy may be used at different time points, with different goals:

• Neoadjuvant radiation therapy is given before surgery to try to shrink a tumor. If a tumor is large, shrinking it may help the surgeon remove the entire tumor with wide margins of healthy tissue.
• Adjuvant radiation therapy is given to patients with early-stage disease after surgery to remove the tumor, when there is no longer evidence of disease. Adjuvant radiation is used to treat any hidden cancer cells that may remain somewhere in the body after the cancer has been removed.
• Radiation therapy for advanced or metastatic cancers may be used to shrink tumors, reduce symptoms, decrease further spread and help people live longer. 

Which cancers are treated with radiation?

The table below lists examples of different types of radiation therapy and how they are used for treating cancer. 

Side effects of radiation therapy

Radiation kills cancer cells. Unfortunately, radiation can damage or kill normal cells near the site receiving the radiation. This can lead to side effects, which vary depending on the type, dose, length, and location of the radiation. For people who experience side effects, there may be options for minimizing or eliminating some of these side effects. Most of the effects are temporary and resolve with time, but some of the effects may show up later or persist for months or years after radiation therapy is completed.

• bowel effects
• dry mouth
• fatigue
• fertility issues
• hair loss
• heart damage
• kidney damage
• low blood cell counts
• lymphedema
• nausea, vomiting, appetite changes and weight loss
• secondary cancers
• skin irritation and changes
• swallowing problems
• urinary problems

Bowel effects

Short term problems from radiation to the pelvic, prostate or rectal may include rectal pain, burning, painful bowel movements, bleeding and diarrhea. There are anti-diarrhea medications that can help with these symptoms, which are usually temporary. Laser therapy may stop rectal bleeding caused by radiation. 

Dry mouth

Dry mouth is a common side affect of the radioligand therapy Pluvicto. Some tips for controling dry mouth include:

• Chewing gum or sucking on sugar-free candies or lemon drops. 
• Limit caffeine intake because caffeine can make your mouth drier.
• Stay hydrated. 
• Saliva substitutes are available without a prescription. Products that contain the sweetener xylitol may help the slow of saliva. Biotene is a brand that makes oral products such as toothpaste and mouth wash that can help alleviate dry mouth. 
• Some medications, such as antihistamines can lead to dry mouth. 
• Use a room humidifier to add moisture to the air.

Fatigue

Fatigue is a common affect of cancer and treatment. It can be short-term but may persist months or years after treatment. 

Expert guidelines recommend that doctors ask cancer patients about their level of fatigue during their regular visits. You should report fatigue to your doctor so you can be checked and treated for underlying causes, including depression, sleep disturbances and medication side effects. Although no medications can counteract the fatigue caused by radiation, some options may improve your energy level, including: 

• making sure that your diet is balanced and provides you with adequate nutrition. Ask your doctor for a referral to a nutritionist if you need help figuring out your dietary needs.
• ensuring that you get adequate sleep. 
• staying physically active even when you are tired. This can help improve your energy level. 

Fertility issues

Some radiation therapy can cause early menopause in women and low sperm counts in men. These changes may be temporary or permanent. Options are available for men and women who are diagnosed with cancer and wish to preserve their fertility. It's important to discuss fertility preservation before starting treatment for cancer. 

Hair loss

Radiation therapy can cause hair loss to the area that is being radiated. Sometimes the hair will grow back but may be thinner than the original hair. 

Heart damage

Radiation to the chest may cause heart damage later. Before you start radiation therapy, ask your oncologist what steps they will take to minimize radiation exposure to your heart. Your oncologist may run tests to make sure that your heart function is normal before, during and after radiation. 

Kidney damage

The radioligand, Pluvicto exposes the kidneys to radiation, which can cause kidney damage. Your kidney function will be checked with blood tests before and after treatment.

Low blood cell counts

Some radiation may damage the bone marrow, where blood cells are made. Your oncologist may test your blood during and after radiation, to make sure that your blood counts do not drop too low.

Lymphedema 

Lymphedema is fluid buildup and swelling that can develop in the arms, legs or other part of the body,  after radiation therapy. The swelling and fluid may be mild to severe and can cause pain, infection and loss of mobility. Lymphedema can happen immediately or months or years after treatment. 

Lymphedema is usually managed with special massage and compression garments. This is most effective when it is caught early. In some circumstances, lymphedema that progresses can be managed with surgery. 

Nausea, vomiting and appetite changes

Digestive issues can happen during chemotherapy. Despite these effects, it's important to try to maintain proper nutrition while on treatment. Your body needs calories and nutrients to fight cancer and repair the damage caused by radiation. Several different medications may help reduce nausea, vomiting and diarrhea. Reducing nausea can improve appetite, reduce weight loss and support a balanced diet. If you need help, ask for a referral to a nutritionist.

Risk for secondary cancers

Radiation damage to normal cells can cause a new cancer to develop. It's important to speak with your oncologist about steps they will take to protect other tissue from radiation. It's also important to ask your oncologist how they will monitor you for second cancers after treatment. For example, radiation to the lymph nodes of the neck after breast cancer may increase the long-term risk for thyroid cancer. Knowing this information can help you take steps to detect these cancers early. 

Sexual side effects

During radiation, damage to the skin may make sex painful. Your doctor may recommend avoiding sex during radiation treatment. In men, radiation may damage nerves and affect the ability to have erections. This may be a short-term or longer-term problem. Speak to your doctor about options for managing any sexual side effects that persist after treatment ends.

Skin irritation and skin changes

Radiation can damage skin cells as it passes through the skin to the area being treated. This can lead to pain, swelling, redness, and sunburn-like damage to skin. Overtime, as with a sunburn, the skin may be itchy, dry or flake or peel. There are things you can do to improve the discomfort, such as wearing loose-fitting clothes made of soft fabrics, protecting your skin from sun exposure, using only mild soaps and products approved by your doctor on your treated skin. There may also be medications and creams or ointments that your doctor may prescribe to help ease the skin pain and discomfort from radiation. 

Swallowing problems

Radiation to the head, neck or chest can cause irritation to the mouth and esophagus, which can make eating painful. Certain liquid medications can help to block the pain. 

Urinary problems

Frequent or painful urination or bladder leakage (incontinence) may occur during radiation to the pelvis or prostate. Damage to the bladder can result in chronic bleeding from the bladder. Your doctor may have medications or strategies such as pelvic floor strengthening to improve incontinence and medication to reduce urinary frequency that persists after treatment ends.

Managing side effects of radiation therapy

Depending on the symptom, there may be options for minimizing or eliminating these side effects. Before starting radiation therapy, it's important to talk with your doctor about the following:

• possible treatment side effects, how serious they are, and how likely they are to occur.
• options for managing each side effect.
• who you should contact if you experience a side effect.
• which side effects are serious and should be seen by a doctor right away. 

Some general tips for managing radiation side effects include:

• Stay well hydrated.
• Make sure you get the proper nutrition. Ask for a referral to a nutritionist if you need help. 
• Use a symptom-tracking app to help you keep track of side effects and report them to your doctor. Some hospitals have apps that connect directly to your electronic health records.  
• Consider participating in a clinical trial of new ways to manage radiation side effects. 

Questions for your doctor

Below are some questions to ask your doctor if radiation therapy is part of your treatment plan.

• What type of radiation therapy will I receive? 
• What will my radiation schedule be? 
• Is brachytherapy an option for me? 
• Are there any precautions that I need to take to keep from exposing others to radiation? 
• Will I need to be in the hospital while receiving radiation therapy? 
• What are some of the side effects I may experience while I'm on radiation therapy? When am I most likely to experience them?
• What are the serious side effects I should look for? Who should I contact if I experience them? 
• Are there any medications or steps that I can take to avoid or lessen side effects? 
• How will you monitor me while I'm on radiation therapy? 
• What are the long-term effects that I should look for? Who will monitor me for long-term effects?