Pituitary Adenoma
The pituitary is a small gland at the base of the brain. It makes hormones that control other glands in the body.
These hormones include:
- Prolactin: used for breastfeeding.
- Growth hormone: controls body growth and how the body uses sugar and fats.
- Thyroid-stimulating hormone: this causes the thyroid gland to make hormones that effect metabolism.
- Adrenocorticotropic hormone (ACTH): this controls how the body makes cortisol when stressed.
- Luteinizing hormone (LH): this controls the menstrual cycle in women.
- Follicle stimulating hormone (FSH): this controls sperm production in men.
A pituitary adenoma is a non-cancerous tumour of the front pituitary gland. Pituitary adenomas can be:
Non-functioning: which means they do not make extra hormones.
Functioning: which means they make more hormones than usual.
Radiation Therapy and Pituitary Adenoma
The best person to talk to about radiation therapy for pituitary adenoma is a radiation oncologist. A radiation oncologist is a specialist doctor who is part of the team that takes care of people having radiation therapy.
You can ask your doctor for a referral to a radiation oncologist to learn if radiation therapy is an option for you.
The Treatment Team
Doctors make a treatment plan for each person based on the:
- type and size of adenoma
- what other treatments have been tried
- the person’s health.
The type of treatment a person gets is worked out by a team of doctors and health professionals often called a Multidisciplinary Team.
A highly trained radiation oncology team takes care of people having radiation therapy. This includes radiation oncologists, radiation therapists, medical physicists and radiation oncology nurses.
Treatments for Pituitary Adenomas
Treatments include observation, medical therapy, surgery, and radiation therapy.
Observation
Small pituitary adenomas that are picked up by chance and not causing symptoms may not need treatment right away. In these cases, doctors keep an eye on the tumour with regular scans.
Medical Therapy
Doctors may treat pituitary adenomas making extra hormones with medicine that stops this. The medicine also controls the growth of the adenoma. The doctor will choose a medicine that works for the type of hormone being made by the adenoma.
Surgery
Doctors use this option for functioning adenomas that are not responding to medicine or if the tumour is pressing on other body parts.
Doctors operate through a small cut made under the upper lip or at the back of the nose. If the doctor cannot safely reach the adenoma this way, surgery may be done through the skull.
Doctors may use radiation therapy after surgery if they cannot remove the whole tumour or if it grows back.
In some cases, doctors offer radiation therapy as the main treatment if the pituitary adenoma is not making extra hormones and surgery is not an option.
Types of Radiation Therapy Used for Pituitary Adenoma
There are 2 types of radiation therapy used to treat pituitary adenoma:
Stereotactic Radiosurgery (SRS)
This is a single dose of highly focused radiation therapy. Radiation oncologists use SRS for small tumours that are a safe distance from sensitive areas such as the optic nerve.
Fractionated (stereotactic) radiation therapy
This is a series of small doses of radiation, given 5 days a week for about 5-6 weeks. Radiation oncologists use this for larger adenomas or if the tumour is close to sensitive areas, such as the optic nerve.
Radiation therapy is very effective for slowing the growth of adenomas.
For functioning adenomas, the goals of treatment are to stop them growing and drop hormones to normal levels.
Radiation therapy can control hormone levels in 50-80% of cases, but it can take a few years for hormone levels to normalise.
General Information About Side Effects of Radiation Therapy
Radiation therapy is more effective with fewer side effects than ever before.
Recent advances mean radiation oncologists can effectively treat the cancer while getting less radiation on healthy body parts. This means much fewer side effects.
Side effects from radiation therapy vary between people, even for those having the same treatment.
While some people feel no side effects, some feel mild side effects, such as tiredness or skin redness during and/or just after treatment. These usually get better within a few weeks.
The treatment team will offer advice and medicine to help with side effects.
Serious side effects that start later (months to years after the radiation therapy) are rare.
Before starting treatment, your radiation oncologist will talk to you about side effects and answer your questions.
The side effects of radiation treatment can be split into 2 groups:
- Early side effects which occur during and shortly after radiation treatment.
- Late side effects which can occur months to years after radiation treatment.
For more information, go to the Potential Side Effects page.
Early Side Effects of Radiation Therapy for Pituitary Adenoma
Short-term side effects that can occur during or just after radiation treatment include:
- fatigue
- headache
- nausea and/or vomiting
- skin redness
- patchy hair loss.
These side effects usually get better 1-2 weeks after treatment.
Late Side Effects of Radiation Therapy for Pituitary Adenoma
Late side effects that can occur months to years after radiation treatment include:
Pituitary hormones: Radiation treatment may cause a drop in normal pituitary hormones. This happens to 30-50% of people around 5-10 years after treatment. This risk increases slowly so doctors usually keep an eye on hormone levels over the long-term.
Eyes and optic nerves: Radiation therapy can damage the optic nerves which can lead to loss of sight. The risk is higher when the tumour is close to the optic nerve or if doctors use stereotactic radiosurgery. If doctors use fractionated radiation therapy the risk is very low.
Stroke: There is a very small increase in the risk of stroke.
Cancer: Secondary cancers are a very rare side effect.
Other Useful Resources for Pituitary Adenoma
Find additional information about cancer types, research groups, and support groups.
Radiation Oncologist
The best person to talk to is a radiation oncologist. You can ask your doctor for a referral to find out if radiation treatment is right for you.
GPs and Health Professionals
Information for any health professional involved in a patient's cancer care with a particular focus on primary care providers.
Talking to Your Doctor
Your GP or other doctors in the cancer team can organise a referral to a radiation oncologist.
Treatment Centres
Search and find your closest Radiation Oncology Treatment Centre.
