Endocrine (hormone) problems

Some cancer treatments can damage your endocrine glands. These glands produce hormones that control the way your body works. This includes:

  • your growth
  • when you go through puberty
  • being able to get pregnant or make someone pregnant (fertility)
  • your metabolism (the way and speed at which your body processes energy)
  • your energy levels.

The problems you may have depend on which glands have been affected. This will depend on the treatment you had, and the area of the body that was treated.

Your doctor or nurse will tell you if your treatment may cause any endocrine problems. They will check for signs of problems at your follow-up appointments. They usually do this by doing blood tests. If you have any problems, your doctor will refer you to an endocrinologist. This is a doctor who specialises in hormone problems.

Endocrine problems can usually be treated with hormone replacement. This may be given as tablets, creams, injections or patches, depending on which treatment you need.

Endocrine (hormone) problems

Different glands in the body make hormones. Hormones are chemicals that control different things. These include:

  • your growth
  • when you go through puberty
  • being able to get pregnant or make someone pregnant (fertility)
  • your metabolism (the way and speed at which your body processes energy)
  • your energy levels.

Some cancer treatments may damage certain glands, causing endocrine problems. This depends on the treatment you had, and the area of the body that was treated.

Your doctor or nurse will tell you if your treatment may cause any endocrine problems. They will check for signs of problems at your follow up appointments. They usually do this with blood tests.

If you have any problems, your doctor will refer you to an endocrinologist. This is a doctor who specialises in hormone problems. Most problems can usually be treated easily by replacing the missing (or low) levels with hormone therapy. You may need to take these for the rest of your life. You may have these as tablets, cream, gels or patches. If you need growth hormone, you might have it as an injection. Your endocrinologist will explain the treatment to you.

Problems depend on the glands that are affected and the hormones they make. The ovaries and the testicles also make hormones. We have included information about some glands that may be affected. If you are worried about these problems or have any symptoms, let your doctor or nurse know straight away. Other conditions can cause them, but it’s always important to get them checked.


Pituitary gland

The pituitary gland makes many different hormones. These act on other glands to produce more hormones. Hormones produced by the pituitary gland include growth hormone and the hormones you need for fertility.

The pituitary is at the base of your brain. Treatments that can affect the pituitary are radiotherapy or surgery to the brain.


Thyroid gland

The thyroid gland is at the front of your neck, just below your voicebox. It makes hormones that control your:

  • metabolism
  • growth
  • development
  • body temperature.

Radiotherapy and chemotherapy can affect the thyroid and stop it working properly. In some people, this may cause the following conditions after treatment.

An underactive thyroid (hypothyroidism)

This is when your thyroid doesn’t make enough of a hormone called thyroxine. It is usually caused by radiotherapy damaging the thyroid. It can also happen after high doses of chemotherapy for a stem cell transplant. It can cause tiredness, muscle cramps and weight gain. It can be easily treated by taking a tablet every day to replace the thyroxine.

An overactive thyroid (hyperthyroidism)

This is when your thyroid makes too much thyroxine, but this is a less common problem. Symptoms include:

  • losing weight without trying
  • feeling anxious
  • having a small lump in your neck.


Adrenal glands

There are two adrenal glands, which sit on the top of each kidney. They make different hormones, such as cortisol. Cortisol is a steroid which keeps your blood sugar stable. It also helps your body cope with physical stress, such as infection or injury.

The adrenals need a hormone produced by the pituitary gland to make cortisol. If the pituitary is not making enough of this hormone, the adrenals cannot make enough cortisol. This may cause a condition called central adrenal insufficiency. Symptoms of this can be mild. They include:

  • tiredness
  • weakness
  • dizziness
  • tummy pain
  • never feeling hungry.

Or you might not have any symptoms until your body is put under stress, for example, if you have an infection. Symptoms can then include:

  • vomiting
  • diarrhoea
  • feeling dizzy
  • being thirsty.

It is usually possible to treat adrenal insufficiency easily with a drug called hydrocortisone.


General endocrine problems

These are some common endocrine problems. Your doctor or nurse will tell you if any other endocrine problems may affect you. We have listed some of these below.

Problems with growth

Treatment can affect growth. This can happen if you’ve had chemotherapy, or if the pituitary gland is damaged (see above). Problems might only be short-term. Once you finish your treatment, your growth will usually go back to normal. But sometimes growth can be affected long-term.

If you have already been through puberty when you have treatment, it might not affect your growth much. You may feel tired (fatigue), or your bones may be less dense.

Your doctor or nurse will monitor you closely after treatment. If there are any signs of a problem, they might talk to you about having growth hormone treatment. If you’re worried about your growth, always tell your doctor or nurse.

Problems with fertility

The pituitary gland, thyroid, ovaries and testicles all produce hormones that control puberty and fertility. If a treatment affects one of these areas, it might also affect your fertility. These treatments may include radiotherapy to the brain or lower tummy area (pelvis), or some types of chemotherapy and surgery. These changes may be temporary. Your doctor or nurse will tell you more about this.

If treatment is likely to affect fertility, there are different things that can help. We have more info about cancer treatments and fertility.

Low levels of sex hormones

If you have surgery involving the ovaries or testicles, it can cause the levels of your sex hormones to be low. Low levels can also happen because of certain chemotherapy drugs or radiotherapy to the pelvis. You may have symptoms including low energy and not feeling interested in sex. You can talk to your doctor or nurse if you are worried about this. It is usually easy to treat with hormone replacement therapy.