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Late and long-term effects of treatment

Most people have at least some side effects during cancer treatment. But many cancer survivors are surprised when they still have side effects after treatment has ended. These are called late or long-term effects.

Learning about this can be worrying. But knowing what the possible side effects are and what to watch for can make it easier to talk to your doctor about any problems you have after treatment.

Whether you’ll experience late or long-term side effects will depend on the type and stage of cancer you had, as well as the treatment you received and how your body responded to it.


Fatigue is a very common side effect of cancer treatment. Fatigue for cancer survivors can be very different from normal tiredness. It doesn’t always go away with rest or sleep. Fatigue can go on for weeks or months after treatment. It is one of the most common long-term effects during the first year of recovery. It can have a serious effect on quality of life.

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Pain is another very common side effect. Pain is common among survivors of breast, prostate, lung and colorectal cancer. Cancer treatments such as chemotherapy, radiation therapy or surgery can injure nerves and cause pain and numbness in certain areas of the body. Some people may have pain in a missing limb or breast. This is called phantom limb pain. Whatever type of pain you have, it’s important to get relief. Tell your doctor about the pain and how it affects your life.

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Learning and memory problems

Many cancer survivors have problems with learning and memory during and immediately after treatment. If you’ve received high doses of chemotherapy or radiation therapy to the brain, you have an increased risk for problems with memory and concentration. This includes survivors treated for cancers such as breast cancer, lung cancer, brain tumours, lymphoma or melanoma.

When chemotherapy affects the way the brain functions this is sometimes called “chemo-brain.” High doses of radiation to the brain (cranial radiation) are more likely to result in long-term changes in mental or emotional functioning. High doses of radiation are needed to treat many brain tumours. Radiation to the brain given along with intrathecal chemotherapy can also increase the chance of cognitive changes.

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Nervous system changes

Sometimes cancer treatment (such as surgery or certain chemotherapy drugs) can cause nervous system damage or neuropathy. Symptoms of nervous system damage include:

  • tingling, burning or numbness in your hands or feet
  • sudden sharp pain
  • loss of balance, difficulty walking or clumsiness
  • being more or less sensitive to heat and cold

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Lymphedema is swelling that occurs usually in the arm, leg, face or neck from buildup of lymph fluid. Lymphedema is usually caused by either removal or damage of lymph nodes due to surgery or radiation therapy. You may be at risk of lymphedema if you have had surgery or radiation therapy for melanoma of the arms or legs, prostate cancer, cancer of the female or male reproductive organs or other cancers that have spread to the lower abdominal area.

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Cancer survivors are at risk for bone and joint problems, especially survivors of breast and prostate cancers. Osteoporosis is a common late effect of cancer treatment. Osteoporosis weakens the bones, causes them to become very fragile and break (fracture) more easily. Osteoporosis can exist for years without symptoms. Chemotherapy, steroids and hormone therapy can increase your risk of developing osteoporosis.

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Mouth and teeth problems

Many cancer survivors develop problems with their mouth or teeth. These problems, which may have begun during treatment, may last a long time before they eventually go away. In some cases, they are permanent. Sometimes, problems develop months or years after treatment has ended. Surgery or radiation therapy to the head or neck for head and neck cancers and certain types of chemotherapy can increase the risk of having mouth or teeth problems. Problems may include dry mouth, tooth decay, taste changes, sore mouth, difficulty swallowing or changes to the jaw bone (osteoradionecrosis or trismus).

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Vision changes

Vision changes can occur when radiation therapy to the head or neck damages the blood vessels of the eye or optic nerve. Vision changes most often occur long after radiation therapy is finished and are more likely to happen when high doses of radiation are given. Vision problems caused by radiation therapy include dry eyes, vision loss or cataracts. Steroid therapy can increase the risk of eye problems, such as cataracts.

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Changes in weight

Some survivors may have problems with weight gain or weight loss. Certain types of chemotherapy, such as those used in breast cancer treatment, can cause weight gain and can increase the percentage of fat tissue while also causing a decrease in muscle mass. Some cancer survivors may lose weight and muscle tone because of a loss of appetite.

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Decreased thyroid function

The thyroid is part of the body’s endocrine system and makes hormones that help control normal metabolism in our body. Radiation to the neck as part of treatment for certain cancers, such as head and neck or Hodgkin lymphoma, can cause decreased thyroid function (hypothyroidism). Hypothyroidism can cause extreme fatigue, dry skin and hair, hair loss, difficulty losing weight or weight gain, intolerance to cold and menstrual problems.

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Menopausal symptoms

Menopause occurs naturally as women age, usually when a woman reaches her early 50s. Women treated for some types of cancer may experience early menopause as a side effect of certain cancer treatments such as chemotherapy, radiation therapy to the pelvis or surgery to remove the ovaries. This is known as treatment-induced menopause.

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Fertility problems

Some cancer treatments lead to fertility problems. Infertility (the inability to conceive a child) is only temporary for some survivors, but in other cases it can be permanent. Your age and whether or not you already have children can play a part in how you deal with the news of infertility. While all side effects are upsetting, this one can be devastating. You may feel a great sense of loss or grief, or be very angry, sad or anxious that cancer and its treatment caused these changes to your body.

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Digestive problems

Chemotherapy, radiation therapy or surgery can cause problems with the digestive system. Digestive problems, such as constipation, diarrhea or nausea and vomiting can occur during treatment, but they can also be a long-term effect for cancer survivors. Some chronic digestive problems, such as constipation, can occur as a result of physical damage or can be a side effect of certain pain medicines used after treatment. Digestive problems can result in the body not being able to absorb nutrients as well.

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Bladder problems

Bladder problems can happen after treatment for bladder, prostate, colorectal, ovarian or other cancers. This can include loss of bladder control or urinary incontinence. Bladder damage can occur from surgery, certain types of chemotherapy or radiation therapy to the pelvis.

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Bowel problems

Bowel problems can happen after treatment for bladder, prostate, colorectal, ovarian or other cancers. Bowel damage can occur from surgery or radiation therapy to the pelvis.

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Heart (cardiac) problems

Heart problems can occur after treatment for cancer. Some common problems include inflammation of the heart muscle, congestive heart failure or heart disease. The main causes of heart problems in adult cancer survivors include radiation therapy to the chest or chemotherapy using anthracycline drugs like doxorubicin (Adriamycin), daunorubicin (Cerubidine) or cyclophosphamide (Cytoxan). People who received high-dose chemotherapy, both radiation therapy to the chest and chemotherapy or those aged 65 or older are at increased risk for heart problems after treatment.

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Lung problems

Chemotherapy or radiation therapy to the chest may cause lung problems. Cancer survivors who received both chemotherapy and radiation therapy to the chest are at increased risk. Some chemotherapy drugs that increase the risk of lung problems include bleomycin (Blenoxane), carmustine, prednisone, dexamethason and methotrexate. Late effects include changes in lung function, thickening of the lining of the lungs, inflammation of the lungs or difficulty breathing.

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Second cancers

Unfortunately, cancer survivors are at an increased risk of developing a second cancer. People at highest risk are those who have received both chemotherapy and radiation therapy.

Second cancers may develop anytime after chemotherapy, sometimes 15 years or more after treatment has finished. The most common types of second cancers after chemotherapy are acute leukemia (the most common), non-Hodgkin lymphoma, bladder cancer and sarcoma.

The most common second cancers that develop after radiation therapy are sarcomas of the bone and tissue, acute myelogenous leukemia, and some tumours like breast or bladder cancer. While a second cancer may develop several years after radiation treatment, most don’t occur until 10 to 20 years (or more) after exposure to radiation.

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Within or into the fluid-filled space around the brain and spinal cord.

For example, during intrathecal chemotherapy anti-cancer drugs are injected directly into the fluid-filled space around the brain and spinal cord.


The gland in the neck, on either side of the trachea (windpipe) just below the larynx (voice box), that makes and releases hormones involved in growth and metabolism.

Also called the thyroid gland.


The time in a woman’s life when her ovaries stop producing estrogen and she has not had a menstrual period for 12 months. Most women start menopause between 45 and 55 years of age.

Menopausal means referring to or having to do with menopause, as in menopausal symptoms.

Sometimes referred to as change of life.

See also premenopause, perimenopause and post-menopause.


Dr David Huntsman and Dr Sohrab Shah Comparing genomes between ovarian cancer subtypes

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