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Selective internal radiation therapy (SIRT)

Selective Internal Radiation Therapy (SIRT): SIR - Spheres

the Revolutionary SIRT method - therapies allows to carry out a liver cancer therapy even at a stage a metastasis. It is based on the technologies promoting radiation delivery directly to the place of a tumor. SIR - spheres ® are delivered through the catheter placed in a femoral artery in the top part of a hip and passed through a hepatic artery (the main blood vessels of a liver) to a tumor.

of the Sphere get with blood to a tumor on vessels where they destroy tumor cells from within.

Selective Internal Radiation Therapy (SIRT) is a revolutionary method in liver cancer therapies, the Israeli doctors uses new technologies for delivery of radiation directly to cells of a tumor and metastasises.

Usual radiation therapy can be applied only to limited parts of a body and it has an adverse effect on nearby fabrics. SIRT - therapy, on the other hand, includes delivery of millions of microscopic radioactive spheres, so-called SIR - spheres ®, directly to liver tumor cells where they selectively irradiate a tumor. The special-purpose character of SIRT - technology allows doctors to deliver in 40 times more to radiation to a liver tumor, than it would be possible when using usual radiation therapy.

The anticarcinogenic effect showed good results only for treatment of a liver and is ineffective at a cancer therapy of other bodies, such as lungs and bones.

The SIRT technology - process

Use of millions of microscopic radioactive spheres called by SIR - spheres ®, in the course of SIRT allow to make targeting and destruction of a tumor in the liver inaccessible to other ways of therapy. In difference from the current radiotheraphy, usual procedure, very specific nature of process of SIRT increases efficiency in murder of cells of cancer at minimization of harmful side effects by surrounding healthy fabrics.

SIR - spheres ® are delivered through the catheter placed in a femoral artery in the top part of a hip and passed through a hepatic artery (the main blood vessels of a liver) to the place of a tumor. Microscopic spheres, each about 35 microns in size (one thirds of diameter of a hair) which are connected with an element yttrium - 90 (At - 90), pure a beta - an element with physical half-decay about two and a half in the afternoon. Microspheres appear in a trap in the vascular course of a tumor where they destroy tumor cells due to decrease in its blood supply (effect of an embolism) and through local radiation damages of DNA of cancer cells. Radiation entirely contains in a body of the patient and constantly within about two weeks therapy continues so far, it is brought out of an organism.

Treatment with SIR - spheres
® uses normal physiological process to reach cancer fabric. Healthy tissues of a liver receives the most part of the blood through a portal vein, and tumors of a liver receive the vast majority of their blood supply of a hepatic artery. As the result, a kateterization of a hepatic artery allows to carry out tergetingovy therapy of cancer of liver.

Unlike chemotherapy which is carried out by repeated cycles SIRT - spheres usually enter to the patient for two separate procedures. One course is given the right share of a liver and one left share, with the period at least one month. Treatment is carried out on an outpatient basis, patients are written out home within 24 hours.

Results of treatment of patients Treatment tarketingovy radio - therapy, as a rule, is not considered by

as the main treatment, but was shown that the combined cancer therapy radiotheraphy and chemotherapy is more highly effective, than only when using chemotherapy.

Clinical tests of SIR - spheres ® were carried out within strict scientific protocols in large clinical hospitals and the oncological centers. A phase I, II and III of test were complete. In Australia and New Zealand, most of patients had the diagnosis an average (metastatic) cancer of a liver while in Hong Kong, primary cancer of a liver was prevailing.

As a rule, patients with a secondary cancer of a liver treated by association of introduction of SIR - spheres ® in a hepatic artery with chemotherapy (out of clinical tests, most of patients are treated by use by system chemotherapy). Results for both groups of patients showed results above, than other forms of treatment. In both Asian and Australian tests, some patients with very started cancer of a liver reached a situation when their tumors were removed in the surgical way as continuation of treatment after application of SIR - spheres ®.

Criteria for treatment of patients of SIR - spheres ®

Having in torichny (from kolorektalny primary) a liver cancer with metastasises

the Having damages of a liver as the main diagnosis

the Having rather healthy liver, well functioning

of SIR - the sphere ® contraindications

the Completed many courses of radiotheraphy of a liver

Ascites or with a clinical liver failure

With strongly broken secretory function of a liver

of the Tumour, giving in to a surgical resection for treatment

Preliminary diagnostics show considerable outflow of hepatic arterial blood to a stomach, a pancreas or intestines

Passed treatment with kapetsitabiny within the last two months or patients who will pass treatment with kapetsitabiny at any time after treatment of SIR - spheres ®

Side effects of targetingovy radiotheraphy

Besides contraindications and precautionary measures, serious side effects, such as gastritis and stomach ulcer which can develop within several weeks after treatment are often observed. Not to allow it, to patients the supporting therapy - drugs for the first month is appointed. Many patients feel sluggish and nausea with a bad appet within several days can develop, but it falls down with time and drug intake. At some patients small temperature increase which can last about one week can develop. Others can feel belly-aches within several hours after introduction of SIR - spheres ®, but it is easily treated by means of drugs.