Treatments in nuclear medicine
How radioactive medicines can treat certain diseases from inside the body, targeting the cells that need treatment.
How it works: treating from within
These treatments use a radioactive medicine that targets diseased cells. Once there, it delivers radiation directly to those cells. The radiation travels only a very short distance, from a few millimetres to less than a millimetre. This helps limit damage to nearby healthy tissue.
These treatments are called radionuclide therapy or radioligand therapy. The medicine is usually given by injection or through a drip into a vein. Some treatments are taken as a capsule.
Theranostics: a scan first checks whether a targeting molecule reaches the diseased cells. If it does, a treatment using the same targeting molecule may be suitable. This helps doctors identify patients who are more likely to benefit.
- Radioactive iodine: the longest-established treatment. It is used for an overactive thyroid, including Graves’ disease and overactive thyroid nodules, and after surgery for certain types of thyroid cancer. You take it as a capsule.
- Lutetium-177-PSMA: for some advanced prostate cancers, when a PSMA PET scan shows that the targeting molecule reaches the cancer cells.
- Lutetium-177-DOTATATE: for certain neuroendocrine tumours.
- Radium-223: for prostate cancer that has spread to the bones.
- Radioembolisation (SIRT): tiny radioactive beads are delivered directly to tumours in the liver through a thin tube called a catheter.
- Radiosynoviorthesis: an injection into an inflamed joint, such as the knee, to reduce inflammation.
Research is progressing rapidly. New treatments are being studied, including for other types of cancer. Some are available through clinical trials.
Your preparation usually includes:
• A consultation with the nuclear medicine specialist, who explains the treatment, its expected benefits and possible side effects.
• Blood tests and often a scan to check whether the treatment is suitable for you.
• Your written consent to treatment.
• A pregnancy test if you could become pregnant. Both women and men receive advice about contraception during and after treatment.
Depending on the treatment, you may go home the same day or stay in the hospital for one night in a room with special radiation shielding. During your stay, visits are limited to protect those close to you. You remain in contact with the healthcare team and can bring your phone, books or a tablet.
Some treatments are given in several sessions, called cycles. For example, lutetium-177-PSMA is usually given for up to six cycles, six weeks apart. Lutetium-177-DOTATATE is usually given for four cycles, eight weeks apart.
These treatments are generally well tolerated. Side effects depend on the medicine used. The most common include:
• Tiredness lasting a few days.
• Nausea, usually short-lived.
• A dry mouth, particularly with PSMA treatment.
• A temporary fall in blood cell counts, which is why you will have regular blood tests.
You will receive clear information about your own treatment. Contact your healthcare team if you develop a fever, notice unusual bleeding or feel unwell.
After some treatments, your body continues to give off some radiation for a few days after treatment. You will receive written instructions tailored to your treatment. These may include:
• Keeping some distance from young children and pregnant women, and keeping close contact brief.
• Sleeping alone for a few nights.
• Sitting down to urinate, flushing the toilet twice and washing your hands thoroughly.
• Avoiding long journeys seated close to other people on public transport.
• Avoiding pregnancy or fathering a child for the period specified by your team.
These precautions are temporary. They protect those around you while allowing you to continue many of your usual activities.
After treatment, you will have blood tests and scans to check how well the treatment is working and how your body is coping with it. The nuclear medicine specialist works with your oncologist, endocrinologist or urologist, who remains your treating specialist.
This information is general and does not replace advice from your doctor. Always follow your hospital’s instructions.
