Long-term and Late Effects of Cancer

Living through cancer can be exhausting for the body and mind, which can cause fatigue and sleep problems.

Cancer-related fatigue

Cancer-related fatigue is the most common long-term effect of cancer treatment. Fatigue is different than being tired. It might not improve much or at all with rest. Many cancer survivors have fatigue for months or even years after cancer treatment.

Sleep problems

Sleep problems are usually related to more than one thing. Other health problems, pain, medicines, caffeine, shift work, and coping methods can all cause sleep problems after cancer treatment.

Osteoporosis

Cancer treatment that affects your hormones can make your bones weak and more likely to break. Low bone density is called osteopenia and very low bone density is called osteoporosis. Osteopenia that isn’t managed can eventually become osteoporosis. But you can take steps to lower your risk of this happening.

Joint or muscle pain

Some cancer treatments can cause joint or muscle pain. These include chemotherapy (chemo), steroids, and hormone therapy. Sometimes, these symptoms will improve over time. People who aren’t physically active may have a higher risk of these problems.

Bowel or bladder problems

Cancer treatments that damage your bowel or bladder can cause long-term or late effects. The most common causes of this are surgery and radiation to the abdomen (belly) or pelvis.

Common bowel and bladder problems include:

• Bowel blockage (obstruction) caused by scar tissue (adhesions)
• Difficulty urinating or emptying your bladder completely (urinary retention)
• Difficulty controlling your bladder causing leakage (urinary incontinence)
• Difficulty or inability to control your bowel movements (bowel incontinence)
• Bladder infection or urinary tract infections (UTIs)

Changes in memory, thinking, and focus can be caused by types of cancer treatment, such as radiation to the brain or chemo. The medical term for these changes is cognitive impairment. But some people call this chemo brain or brain fog.

Make sure your cancer care team knows about any changes you have in memory, thinking, or focus. If you have new or worsening changes, tell them right away. These could be signs of a more serious problem.

Increased risk of cavities and tooth loss

Different cancer treatments can increase your risk of cavities and tooth loss.

Chemo can damage your tooth enamel, increasing your risk of tooth decay and cavities.

Radiation to your head, neck, or brain can permanently damage the glands that make saliva. This can cause dry mouth, which increases your risk for cavities and tooth loss.

If you’ve received these cancer treatments, try to see a dentist at least once every 6 months to help keep your teeth healthy.

Osteonecrosis of the jaw (ONJ)

ONJ is a rare but serious effect of certain cancer treatments. It happens due to poor blood flow to the jawbone. Without blood and oxygen, bone cells in the jaw start to die and can start to show through the gums.

Cancer treatments that can cause ONJ:

• Radiation to the jawbone
• Certain medicines used to prevent bone loss or osteoporosis, called bisphosphonates

This is more common after tooth infection, extraction, or trauma, and it can be hard to treat. The main symptom is pain in the jaw. In some cases, the bone actually breaks. Sometimes the fractured bone heals by itself, but often the damaged bone will have to be repaired with surgery.

To help prevent this problem, people getting treated with bisphosphonates or radiation to the mouth or throat area need to see a dentist to have any problems with their teeth treated before treatment is started. In some cases, teeth may need to be removed. Good oral hygiene by flossing, brushing, making sure that dentures fit properly, and having regular dental check-ups may help prevent ONJ.

Some types of cancer treatments affect parts of the body that make hormones. This can lead to health problems depending on what hormones are affected.

Low levels of thyroid hormones

Certain cancer treatments can damage the thyroid gland, which makes thyroid hormones.

These treatments include:

• Radiation to the head and neck
• Surgery to remove your thyroid gland (thyroidectomy)
• Total body irradiation
• High doses of chemo
• Certain types of immunotherapy and targeted therapy
• Radioactive iodine used for certain thyroid cancers

Most thyroid problems related to cancer treatment are due to low levels of thyroid hormone (hypothyroidism). The most common signs and symptoms of an underactive thyroid are:

• Fatigue or sleep problems
• Hair loss
• Dry skin
• Muscle cramps
• Anxiety or depression
• Feeling colder than usual

People treated for thyroid or head and neck cancers have the highest risk of thyroid problems after cancer treatment. If you have had these cancers, your doctor may check your thyroid levels every so often.

Low levels of estrogen and testosterone

Some cancer treatments affect the ovaries and testes, which help make the hormones estrogen and testosterone, also called sex hormones.

People with breast, ovarian, testicular or prostate cancer have the highest risks for hormone problems related to cancer treatment.

Treatments that can affect the sex hormones:

• Surgery to remove ovaries (oophorectomy) or testes (orchiectomy)
• Radiation to the ovaries, prostate, or pelvis
• Medicines that temporarily stop the ovaries or testes from making hormones
• Chemo
• Steroids

Low levels of estrogen and testosterone can cause hot flashes, cognitive changes, bone loss, changes in sex drive, and weight gain. In addition:

• Low levels of testosterone can cause difficulty having or keeping an erection.
• Low levels of estrogen can cause vaginal dryness and pain during sexual activity.

Many of these symptoms are like those of menopause. But they may be worse because the hormone levels drop quickly, rather than slowly over time like in natural menopause. For those who get menstrual periods who haven’t gone through menopause yet, menstrual periods might be lighter or happen less often. Some people stop having periods altogether. If cancer treatment only blocks hormones temporarily, periods might come back after treatment. If your periods do not return to normal after treatment, talk with your cancer care team.

High doses of chemo, especially ones that are platinum-based, and radiation to the head, ear, or brain can cause damage and hearing problems in one or both ears. Certain antibiotics and non-chemo medicines can also cause hearing loss.

Hearing loss related to cancer treatment is often permanent, but a hearing aid might help. Your cancer care team may refer you to an ear, nose, and throat (ENT) specialist or audiologist to help with hearing loss.

Radiation to the head or eye, as well as some chemo drugs, targeted therapies, immunotherapies, and hormone therapies, can cause changes in your vision. They may also cause eye conditions such as cataracts and glaucoma. Other effects to your eyes include dryness, redness, swelling, sensitivity, or irritation.

If you have or had vision changes from cancer treatment, ask your health care team about seeing an eye doctor (ophthalmologist).

Some cancer treatments might damage your heart. These problems don’t usually show up until years later. People who smoke or have other conditions like high blood pressure, high cholesterol, or diabetes are at greater risk.

Treatments that can damage your heart are described as being cardiotoxic. You might also hear the medical words cardiomyopathy or cardiovascular disease used to describe heart disease.

Cancer treatments that can cause heart problems include:

• Chemo, especially anthracyclines and cisplatin
• Immunotherapy, especially immune checkpoint inhibitors
• Targeted therapy, like VEGF inhibitors and HER2-directed therapy
• Hormone therapy or androgen deprivation therapy (ADT)
• Radiation to the lung, chest, or breast

Some cancer treatments can damage the lungs and cause lung problems. This can happen with chemo such as bleomycin or busulfan, or from radiation to the chest. The risk is higher in people who receive both treatments at the same time. Lung problems can cause:

• Cough
• Shortness of breath
• Wheezing

If you have or had breathing changes from cancer treatment, ask your health care team about seeing a lung doctor (pulmonologist).

Lymphedema is swelling that can develop if you’ve had lymph nodes removed or damaged. It can affect your mobility, self-image, and quality of life. It also increases your risk of a serious skin infection called cellulitis.

The most common cause of lymphedema is surgery or radiation that removes or damages lymph nodes during treatment for breast and head or neck cancers.

It can start at any time, even years after cancer treatment. It’s usually reversible if it is managed before it gets severe.

Many people who go through cancer say they weren’t prepared for the long-term and late mental health effects. Once treatment is complete, a number of emotional concerns can still come up.

The most common types of mental distress among cancer survivors are:

• Anxiety
• Depression
• Post-traumatic stress and PTSD
• Loneliness
• Fear of recurrence
• Feelings of resentment for having a cancer diagnosis or having to undergo treatment
• Feelings of guilt for surviving cancer (survivors’ guilt)
• Concerns of discrimination or being treated differently by others
• Worries about relationships, dating, or having a family later in life

It’s normal to feel some anxiety or other emotions after treatment. But feeling very worried, depressed, or angry can affect many parts of your life, including your relationships, school, and work. With support from family, friends, other survivors, and mental health professionals, many people can still do well and enjoy life after cancer.

Cancer treatments like chemo, immunotherapy, targeted therapy, surgery, and radiation can affect the nerves that lie outside your brain and spinal cord. This can lead to numbness, tingling, or pain, most often in the feet and hands. When this happens, it is called peripheral neuropathy (PN). PN can make it hard to walk, hold things, or do daily tasks.

For some people, the damage can get better slowly over time. But for others, it can be permanent. If you notice these changes, tell your cancer care team. They can help manage the symptoms and protect your safety.

It’s important to talk with your cancer care team about how your cancer treatment may affect your sexuality and fertility. Don’t assume that they will bring it up; you may have to start the conversation. If you aren’t getting the information you need, you can always ask if a referral to a specialist might help.

Fertility

Any cancer treatments that affect the reproductive system can cause fertility problems. Certain types of chemo and radiation to the pelvis, belly, or spine can damage the ovaries and testes.

Sometimes, fertility problems are short-term and get better over time. Others can be permanent. This depends on the type of treatment. Fertility problems can affect anyone, no matter their sex. Cancer treatments are more likely to affect fertility when they are given during or after puberty.

Some people choose to do fertility preservation before cancer treatment. Fertility preservation includes different methods of collecting or protecting a person’s reproductive tissues or organs.

Sexuality

Sexuality is more than just sex. Cancer treatment can cause changes to your sex organs, sexual drive, sexual function and well-being, and body image. Many people don’t get enough information or support to deal with the effects of cancer treatment on their sexuality.

Some people might think it’s silly to worry or ask about sexual problems because compared to having cancer, it’s not “important.” But this isn’t true. When you feel bad or unsure about parts of yourself, it can harm your mental health and relationships with others. If it’s important to you, it’s important.

Many of the long-term and late effects of cancer treatment can affect your sexuality. This is partly because of how they might affect your mental health. For example, some people have physical changes from their cancer treatment. This could include scars, ostomies, prostheses, or physical changes because of effects from certain medicines, such as steroids. After these changes, some people struggle with body image or worry that others will judge or reject them.

Talk with your cancer care team or primary care provider (PCP) if you notice changes in your sexuality. They may refer you to a sex educator, counselor, or therapist. If physical problems are affecting your sexual health or sexual function, they can also connect you with a specialist who can help.

Many cancer survivors say their biggest fear is getting cancer again. Even though second cancers are not common, certain cancer treatments increase your risk for a second (or secondary) cancer. Examples include acute myelogenous leukemia after chemo or breast cancer after radiation to the chest.

Secondary cancers are different from cancer recurrence. Cancer recurrence is when the first, original cancer returns. A secondary cancer is when you get another, new cancer. Both secondary cancers and cancer recurrence can happen in the same or different part of the body as the first cancer.

Secondary cancers aren’t always related to cancer treatment. Some people may be at risk for other types of cancer because of their family history, lifestyle, or environment. Talk with your cancer care team about your risk and what steps you need to take, including routine cancer screenings after cancer.