Late effects of cancer treatment

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Late effects of cancer treatment may occur months or years after treatment has finished. Learn about the types of late effects, how to minimize your risk and where to find more information.

Key points

  • Late effects are side effects of cancer treatment that may start during treatment or may not happen until months or years after treatment finishes.
  • Most teen cancer survivors do not have serious late effects, and your risk of developing them depends on the type of cancer and treatment you had.
  • Types of late effects include fertility, heart, lungs, learning and memory, kidneys, growht and development, thyroid gland, hearing and vision, and secondary cancers.
  • Minimize your risk of late effects by attending all follow-up appointments, leading a healthy lifestyle, and practicing self-monitoring.

What are late effects?

Late effects are side effects of cancer treatment that:

  • may start during cancer treatment and remain after treatment ends, or
  • happen months or years after cancer treatment is finished
  • They happen because cancer treatment has damaged healthy cells, and the effects of the damage may not show up until later.

Remember that most teen cancer survivors do not have serious late effects from treatment. Cancer treatments are improving all the time to lower the risk of late effects. Your risk of developing late effects depends on the type of cancer you had and the treatment you received. The good news is there is treatment for many late effects. Practicing self-monitoring means that any signs of late effects can be caught as early as possible by your health-care provider.

Dealing with late effects can be frustrating. Although therapy was necessary to treat the cancer, you may be angry or disappointed that a new problem was caused by the treatment. Talk to your health-care team if you are having trouble coping with the late effects of your treatment, or if you are worrying a lot about getting late effects in the future.

Types of late effects


Some treatments can have lasting effects on your ability to have a child. You’ll find more information in the section on treatment and fertility.

Heart and lungs

Some types of chemotherapy and radiation to the chest or upper back may cause damage to the heart and lungs.

  • Heart: Your heart may not be able to pump blood as well as it could before. You might feel tired when you exercise, or you might feel more out of breath. If you are at risk, you will be examined at follow-up appointments with tests to monitor your heart function such as an echocardiogram (echo).
  • Lungs: You may feel more easily out of breath. If you are at risk, you will be monitored with lung tests such as pulmonary function tests (PFTs).

Learning and memory

Treatment for some brain tumours, lymphomas, leukemias and/or radiation to the head may cause difficulty with learning, memory or concentration. Check out the section on cognitive side effects of radiation for more information.


Your kidneys clean your blood and make urine (pee). Some types of chemotherapy or radiation to the abdomen (belly) can damage the kidneys, or you may have had a kidney removed as part of your treatment. Your health-care team may monitor how your kidneys are working with blood tests. They will also check your blood pressure and may send a sample of your urine to a lab to be examined for signs of kidney problems.

Growth and development

Some treatments can interfere with how you grow or develop.

  • Radiation to bones, such as those in your spine or in your legs, can prevent them from growing normally. For example, your spine may be shorter or may be more curved.
  • Some medications, such as steroids, may cause bones to be weaker and more likely to break. If you are at risk, your health-care team will monitor for this during follow-up. Monitoring might include bone scans. Your health-care team may also prescribe medicine to help strengthen your bones during and/or after treatment.
  • Radiation to the brain can affect hormones that control normal growth and development. This can often be corrected by taking hormones as a medication.

Thyroid gland

Your thyroid gland is in the front part of your neck. It makes hormones that control your metabolism (the way your body uses energy).

Radiation to the head and neck can damage the thyroid, causing problems that can slow down your metabolism or speed it up. For instance, you might notice you feel tired or weak.

If you are at risk of thyroid late effects, you might be monitored with physical exams of your thyroid. You may also be monitored with blood tests to look for the amount of thyroid hormones in your blood. Problems with thyroid hormones can often be treated with medication, but sometimes they require surgery.

Hearing and vision

Some types of chemotherapy can cause problems with vision and hearing. If you are at risk of these late effects, you might be monitored with hearing tests and tests to check your vision.

Secondary cancers

Getting cancer again as an adult can be a really scary thought for many teens. However, surviving childhood or teenage cancer only slightly raises your risk of developing a new cancer in the future. Some types of chemotherapy and radiation, or a family history of cancer, can increase this risk.

All survivors who have had radiation need an exam every year to check for skin cancer. If you have had radiation to your neck, you will also need a yearly thyroid exam to check for thyroid cancer. Monitoring for other secondary cancers, such as breast or colorectal (intestine) cancers, usually starts when you’re an adult.

It can be scary to think about late effects, but it’s important to remember that most teenagers do not develop serious late effects.

What can I do to minimize the risk of late effects?

  • Attend all of your follow-up appointments. In the future, be sure to visit your health-care provider for yearly check-ups. Be sure that both you and your health-care provider know your cancer and treatment history, so you can be monitored properly. You are the most important link to making sure that all of your health-care providers know everything that is important about your past cancer. Remember, there is a better chance that a late effect can be treated when it is found early.
  • Lead a healthy lifestyle. This will lower your risk of developing health problems in the future, including some late effects. You will learn more about a healthy lifestyle in the section on Cancer and your lifestyle.
  • Practice self-monitoring. Similar to how you may have self-monitored for symptoms and side effects while on treatment, it is important for you to self-monitor for late effects.

Where can I find more information about late effects?

For more information on late effects, check out the set of documents called "Health Links" produced by the Children’s Oncology Group (these apply to teens as well as children). They describe the different late effects, who is at risk of developing them, and what you and your health-care team can do to monitor for them, prevent them, or treat them.

You’ll find the complete list of health links here:

(Tip: Scroll halfway down the page to find the list.)

You can download the MyHealthFinder app from Healthy Survivorship, for iPhone or Android. Designed for young people between 15 and 39, the app supports you in making an individualized survivorship plan.

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Last updated: September 3rd 2019