What is Radium-223 Therapy?
Theranostics is a recently developing field of the medicine. This approach takes body images using a tumor-specific agent to locate the tumor and its metastasis and their potential future locations and it also uses a specific agent with pre-determined therapeutic efficiency for the diseased tissue. This approach enables switching from traditional medicine to contemporary personalized medical procedures.
In Theranostics practices, metastases can be diagnosed and treated with certain agents. For prostate cancer, F-18 NaF PET/CT allows visualization of bone metastases with high sensitivity, while specific and targeted therapies of tumor tissues can be carried out with Radium-223. This is a rather successful example of theranostic procedures.
Contrary to many other types of cancer, most of deaths related to prostate cancer are caused by bone metastasis and complications.
Radium-223 therapy is a treatment modality that can be used upon recommendation of a primary physician for patients with prostate cancer that spread or metastasized to bones. The goal is to damage cancerous cells in bones and cause tumors to shrink and even completely disappear. It is also used to manage bone pain secondary to cancer.
How is Radium-223 Used in Treatment?
Radium-223 is a radioactive element that selectively binds to bone metastases and radiates very short-range and high-energy alpha particles (< 100 μm). Radium-223 dichloride binds to bone metastases by mimicking calcium and then the radiation emitted by high-energy alpha particles kills tumor cells that cause DNA fragmentation. The short-range of alpha particles helps to minimize damage to adjacent healthy tissue and especially to bone marrow. Radium-223 with therapeutic effect based on emission of radioactive alpha particles is the only bone-specific drug that is known to prolong survival. Scientific studies have demonstrated that Radium-223 therapy prolongs average life expectancy. In addition, it helps with pain management and improves the quality of life. Besides all aforementioned advantages, side effects of Radium-223 therapy are very mild, except for temporary decrease in blood count and diarrhea.
Who are the Candidates for Radium-223 Therapy?
Radium-223 therapy is a very specific treatment method and therefore, it may be employed if deemed viable by a primary physician on patients with prostate cancer with only bone metastasis and pain.
Radium-223 therapy may alleviate pain, which is common in cancers that spread to bones. When the therapy is decided, a whole body bone scan (e.g. F-NaF PET/CT, bone scan) is performed prior to treatment. This will allow making sure that correct areas are targeted in Radium-223 therapy.
Is Radium-223 Therapy Safe?
Alpha radiation, which is used for Radium-223 therapy, has a very high energy level. However, alpha radiation travels very short distances (at a range of two to ten cells) due to its nature, which fact helps to impose destructive effect of radiation on cancer cells in bones and unhealthy cells. Minimum radiation exposure of healthy cells makes side effects of Radium-223 therapy negligible, and temporary decrease in blood cell count and rare cases of nausea and diarrhea may be observed.
Preparation before Radium-223 Therapy
It is imperative that you bring all the information and documents listed below upon your visit to the clinic. Information presented in digital media (DICOM, JPEG, PNG, PDF, Microsoft Word (.doc, .docx, etc.) will facilitate faster and easier sharing through e-mail and provide great advantages in assessment of your disease.
●Contact details of you and your primary physician (home/work/cell phone number, e-mail address)
●Most up-to-date medical reports
●Total body bone scan, CT, MRI and 68Ga-PSMA PET/CT, 18F-FDG PET/CT reports and original films/CDs/DVDs.
If needed, your Nuclear Medicine Physician may order 18F-NaF PET/CT or total body bone scan in order to assess your eligibility for treatment and bone mineral density measurement in order to investigate osteoporosis.
You will also be asked to have following blood tests. As these tests are expected to show your condition during treatment, they should have been made at least 2 weeks before the treatment. The tests will be done before the treatment and each treatment cycle.
●Complete blood count
Your physician may order additional blood tests.
Radium-223 therapy does not require dose modification for patients with liver and kidney failure.
Patients with bone fractures or spinal cord compression will be asked to have those conditions treated before the treatment.
You need to make sure minimum 4 weeks have passed from your last cycle, if chemotherapy was administered to you.
We recommend you to take with you loose and comfortable clothes from home since you will be wearing your own clothes throughout the treatment. Short sleeved or large cuffed clothes will help you, since intravenous access will be inserted into a blood vessel on your arm or back of your hand for treatment and concomitant tests.
Since Radium-223 is excreted by intestines, additional supportive measures may be needed for patients with inflammatory bowel disease, such as “ulcerative colitis” and “Crohn’s Disease” or history of intestinal obstruction.
How is Radium-223 Therapy Administered?
Standard Radium-223 therapy consists of six cycles in total with four-week intervals (6 times, each injection lasting one minute).
Radium-223 dichloride solution, which is manufactured for you and ready to be used, will be infused into your body through peripheral intravenous access at the Nuclear Medicine Clinic.
Before Radium-223 is administered, minimum 10 ml of saline will be used to irrigate and check your intravenous access; Radium-223 will be slowly infused and administered over 1 minute, and then your intravenous access will be irrigated with minimum 10 ml of saline again. No pain is felt during the procedure.
Radium-223 dichloride will be rapidly cleansed from your blood following the infusion; its uptake will first occur in bones and bone metastases or it will be excreted to intestines.
Potential Side Effects and Instructions
Most common side effects of Radium-223 therapy are nausea, vomiting and diarrhea (≥ 10%). Temporary decrease in blood counts is also likely.
Patients under treatment should follow the instructions given below:
- Have blood count test done on the specified dates. Notify your physician about any bleeding or symptoms of infection.
- You should sufficiently hydrate by mouth; monitor hydration levels and urine output.
- Inform your physician if you are dehydrated or if any signs of kidney failure develop.
- No limitation is required regarding physical contacts with other people after the treatment.
- Preserve good hygiene during Radium-223 therapy and at least for 1 week following the date of last dose.
– Use the toilet in a sitting position and flush at least twice after each use.
– Immediately wash your clothes contaminated with urine and stool separately from other clothes.
- Your caretakers should wear gloves when touching your bodily fluids and wash their hands afterwards in order to prevent infection.