Medical Services
Radionuclide Therapy (Nuclear Department)
SIR-Spheres and SIRT (2)
Treatment Information
SIR-Spheres therapy is regarded as a regional treatment; that is, the anti-cancer effect is concentrated in the liver and there is no effect on the cancer at other sites. SIR-Spheres are used to treat secondary liver cancer where the cancer originates in the bowel (colon or rectum) and then spreads to the liver. This type of cancer is called metastatic colorectal cancer.
SIR-Spheres is generally not regarded as a cure, but has been shown to shrink the tumours more than chemotherapy alone. Quality of life can improve, and life expectancy may increase. For a small number of patients, treatment with SIR-Spheres can cause marked shrinkage of the liver tumour allowing for surgical removal at a later date.
How Do I Qualify ?
Patients suitable for treatment with SIR-Spheres need to establish that :
- they have non-resectable metastatic colorectal cancer; that is, cancer that originated in the bowel or rectum and has spread to the liver;
- they have the liver as the major site of disease;
- they have sufficient remaining healthy liver still functioning satisfactorily (this can be determined by a simple blood test)
- they meet the pre-selection criteria established by their doctor's pre-treatment testing.
If you meet the criteria above then you may be a candidate for treatment and you can contact one of the treatment centers that specialize in SIR-Spheres therapy. A cancer specialist will then make a decision on your suitability for treatment. In addition, you can take this brochure plus other information from our web site to your doctor and have him or her contact us.
What Are The Side Effects ?
Patients should not have any serious side effects when SIR-Spheres are correctly administered. However, during the infusion of the SIR-Spheres you may experience some pain. If you do, your doctor will provide medication to help alleviate any discomfort during the infusion.
Sometimes patients develop pain in the abdomen that may last for a few hours after the administration of SIR-Spheres, but this can also be treated with medication. Most frequently, patients develop a fever and may experience nausea but these symptoms subside with time and medication.
Patients are often placed on medication for the first month after treatment with SIR-Spheres to alleviate any symptoms of gastritis (stomach upset) and peptic ulceration. Many patients complain of feeling lethargic with loss of appetite for several days after the treatment, but this also subsides with time.
There is the potential of more serious side effects if the SIR-Spheres are incorrectly delivered into the artery supplying blood to the liver. In this case, the SIR-Spheres could be inadvertently supplied to the stomach, duodenum (intestine), pancreas or other organs, resulting in severe side effects. Interventional Radiologists delivering SIR-Spheres are given special training to inform them of this risk and to prevent this from happening.
The dose of radiation is individually prescribed for each patient. If the normal liver tissue receives too high a dose, some patients may develop long-term damage to the normal liver. Because everyone is unique, it is not possible to predict what side effects you may experience. It is always important to discuss SIR-Spheres treatment benefits and potential risks with your doctor and to have realistic expectations of your SIRT treatment. If you have questions about any side effects discussed in this brochure consult your doctor or a member of your health care team.
The Treatment Methodoloy
SIRTEX's method for treating liver cancer is based on innovative microsphere technology, known as Selective Internal Radiation Therapy - or SIRT.
This treatment method takes advantage of the fact that approximately 80% of the blood supply to the liver flows via the portal vein, and only about 20% via the liver artery (hepatic artery). Tumours, by contrast, normally receive their entire blood supply via the liver artery. By gaining access to the liver tumours via the liver artery, the tumours can be directly targeted and irradiated. Surrounding, healthy tissue is therefore largely preserved. Millions of tiny, biocompatible microspheres (beads), called SIR-Spheres deliver the radiation to the tumour. SIR-Spheres are very small, measuring about one-third the diameter of a strand of hair. They contain a radioactive element called yttrium-90, which emits beta rays. SIR-Spheres are injected into the liver artery, and the bloodstream carries them directly to the tumour.
SIR-Spheres reach the tumours wherever they are situated in the liver, so it is not necessary to know exactly how many tumours exist or where they are located. The microspheres lodge themselves in the small vessels feeding the tumour and deliver targeted, high doses of radiation to the tumour and tumour vessels.
The treatment is carried out in three steps :
1) Pre-treatment patient care
2) Catheder insertion/injection of SIR-Spheres
3) Post-treatment patient care
Treatment takes just a few days. The SIRT therapy itself is carried out on Day 1 of the hospital stay. The patient is then monitored in hospital for another one or two days.
Indications and Contraindications
- Indications : SIR-Spheres is indicated for use in the treatment of malignant liver tumours of primary or secondary origin that are not suitable for resection with curative intent.
- Contraindications : SIR-Spheres is contraindicated in patients who have
- had previous external beam radiation therapy to the liver,
- ascites or are in clinical liver failure,
- markedly abnormal synthetic and excretory liver function tests,
- tumours amenable to surgical resection for cure,
- greater than 20% lung shunting (determined by the nuclear medicine breakthrough scan)
- pre-assessment angiogram and MAA nuclear medicine scan demonstrates that significant reflux of hepatic eraterial blood to the stomach, pancreas or bowel,
- disseminated or extra-hepatic disease
- been treated with capecitabine within the two previous months, or will be treated with capecitabine within the two previous months, or who will be treated with capecitabine at any following treatment with SIR-Spheres.
Information from "Sirtex Medical Europe GmbH"
Person in charge : Pr Patrick Flamen
+32 2 541 31 11