Nuclear medicine therapy is an approach to treating cancer that might be used with or after other treatment options, such as chemotherapy and surgery. It won't usually lead to a cure unless combined with other therapies. But for many people it will control symptoms and shrink and stabilize the tumors, sometimes for years. Nuclear medicine therapy is sometimes the best option for people who no longer respond to other treatments.
What makes nuclear medicine therapy effective is the use of radioactive molecules as a drug (molecular radiotherapy). The drug recognizes tumor cells. It's injected intravenously, then circulates in the body, sticks to the tumor cells, delivers radiation directly and causes them to die. Some of the drug never attaches to cancer cells and keeps floating in the blood until the body gets rid of it, mostly in the urine. Over time, the radioactive drug stops giving off radioactivity and stops killing cancer cells. Nuclear medicine therapy is often repeated multiple times to achieve the most benefit.
Nuclear medicine therapy is also called peptide receptor radionuclide therapy (PRRT), targeted radiotherapy, radionuclide therapy, therapeutic nuclear medicine and a theranostic approach to treating cancer.
People with neuroendocrine tumors (NETs), including rare pancreatic NETs, now have wider access to PRRT following the January 2018 U.S. Food and Drug Administration (FDA) approval of lutetium Lu 177 dotatate (Lutathera). This is an important option, as NETs can be widespread throughout the body and hard to remove with surgery.
What you can expect
Once you have a diagnosis and you and your care team have decided that nuclear medicine therapy is the best option for you, you'll be scheduled for treatment. It may take up to a month before you can start therapy while blood and imaging tests are completed, your medications are modified, and therapy is prepared. Usually therapy involves up to four infusion sessions, each usually eight weeks apart.
The treatments are given in an outpatient setting. Plan to be on-site for up to eight hours each time. When you arrive, you'll be cared for by a skilled team of specialists who provide safe and efficient therapy.
Before you start therapy, you're given medications to reduce nausea. Then a small tube (catheter) is inserted into an arm vein through which an amino acid solution drips in. This solution helps protect your kidneys. It flows for about 30 minutes before you start receiving the medication designed to target and kill cancer cells (Lutathera).
Lutathera flows into your vein for 30 to 40 minutes. Then you'll continue receiving the amino acid solution for about 3 hours. Soon after the catheter is removed, you'll be able to leave the hospital.
Care at Mayo Clinic for neuroendocrine tumors
Tailoring nuclear medicine therapy to you
No two people experience cancer or respond to treatment in the same way. For most people, symptom improvement comes after the second dose. Your care team considers many factors when prescribing your nuclear medicine therapy and adjusts it over time.
After each infusion session, you may be asked to undergo a SPECT scan. This scan measures how much nuclear medicine therapy stuck to the cancer cells and how fast the drug is leaving your body. This information guides your care team members as they choose when and how much therapy to give you to kill the cancer and avoid side effects.
After you have completed your therapy, your doctor will ask that you return regularly for follow-up visits, which may include more blood tests and scans.
Possible side effects
Side effects can occur and they depend on your specific therapy and medical condition. It used to be common for people to experience nausea when receiving nuclear medicine therapy, but that has become far less of an issue. Many people even enjoy eating during therapy. Some people notice hair loss, but it's usually only a little and the hair grows back.
Rarely, someone who has had nuclear medicine therapy might develop a cancer of the blood months or even years later.
Note also that traveling after Lutathera treatment might result in travel delays. Talk with your doctor about the advantages and risks of this treatment.
Learning about nuclear medicine therapy
Talk with your care team about what to expect before, during and after treatment, which is usually administered in up to four outpatient visits.
Deciding whether nuclear medicine therapy is right for you
Your nuclear medicine care team considers many factors before prescribing this type of therapy for you. You'll likely undergo a positron emission tomography (PET) scan to help determine whether nuclear medicine therapy is right for you and your cancer.
When a PET scan is needed, a version of the drug that will later be used for nuclear medicine therapy is injected into a vein. The drug floats around in the blood. If the drug bumps into cancer cells, it sticks. However, this version of the drug does not kill cells. Instead, it gives off only a very small amount of radioactivity.
The radioactivity is detected by the PET scanner, which turns this information into a 3D image of the entire body that can show where cancer is hiding. The PET scan can show if the drug sticks to the cancer as expected. In this way doctors use a PET scan to test if someone might be a good candidate for nuclear medicine therapy.
Other treatment options
Mayo Clinic doctors will work with you to review all of your treatment options and choose the treatment that suits your needs and goals. Nuclear medicine therapy is usually given by itself, but it can be combined with other therapies delivered by medical oncologists, radiation oncologists or interventional radiologists:
Nuclear medicine therapy is available at three Mayo Clinic locations
Most people are referred to the team of specialists in nuclear medicine therapy by one of their doctors. Talk with your doctor about whether your condition makes this treatment a good choice for you. Eligibility for this therapy depends on many factors related to the tumor and your overall health.
You may be seen at any one of the clinic's main campuses in Phoenix/Scottsdale, Arizona; Jacksonville, Florida; and Rochester, Minnesota. Each campus has the expertise and technology required to guide you through nuclear medicine therapy. Each location has cyclotrons, PET radiochemistry laboratories and nuclear radiopharmacies, all of which are needed to properly handle nuclear medicine therapy and produce the drugs for PET and SPECT imaging. Each campus also has state-of-the-art scanners, including PET/CT, PET/MRI and SPECT/CT.
Cyclotrons are particle accelerators that create radioactive atoms (radionuclides). These atoms then are linked to drugs and checked for quality and safety per FDA regulations. These drugs are made fresh specifically for the people coming to the clinic that day.
Nov. 26, 2020