Selective intra-arterial radio therapy (SIRT)

Radioembolisation is a method of treating cancer by embolizing (blocking) the blood vessels of a liver tumour with radioactive particles. ŠThis treatment method is used in cases of inoperable (unsuitable for surgery) liver tumours and metastases to the liver. Embolization – blockage of part or all of the radius of a blood vessel, stopping blood flow in vascular formations.

Radioembolization with Holmium-166 radioisotope.

After the radioactive material treatment, the patient’s background radioactivity is measured. If the patient has been treated with a topical approach, the radioactivity is localised to the site where it is injected. After the procedure, a higher background of radioactivity was measured, so patient isolation measures were applied for a certain period of time – the patient stays in a separate ward for a day until he or she is safe to return to home.

SIRT application

International guidelines recommend SIRT as one of the HCC and mCRC tumorsų. It aims to increase overall survival in patients with advancedadvanced stages of HCC tumours in patients with advanced HCC who have received prior treatmentmethods have not been successful. 

For early-stage HCC patients, SIRT also aims to provide access to curative treatments such as, “bridging” pre-transplant, offering tumour control to keep the patient on the transplant waiting list for a longer period of time. It can also be used to shrink patients’ tumours to allow for resection. 

SIRT procedure

The radioembolisation procedure consists of 2 stages – a diagnostic stage and a treatment stage. The two steps are identical, only the amount of radioisotope injected differs. During the diagnostic phase, a small dose of a radioactive agent is injected. This stage is designed to see exactly where the product is going so that the patient can receive a safe treatment. To achieve the best possible effect, special software calculates the dose needed for each focus and patient. This leads to personalised treatment, where the tactic – the dose of the drug and the site to be treated – is personalised to the patient.

In a minimally invasive interventional procedure, holmium microspheres are deposited in the tumour tissue and the beta radiation emitted by the isotope affects the tumour biology and promotes tumour cell death. The Holmium isotope has unique properties, such as additional low-energy gamma radiation and paramagnetic radiation, which make the isotope visible in diagnostic equipment. This allows very precise planning of the procedure and calculation of the dose of radioactivity to be administered individually to maximise the success of the treatment and avoid serious side effects

SIRT course and treatment scenarios

Fast-growing liver tumours have a large number of feeding blood vessels, which is the feature that doctors try to exploit. Their job is to identify blood vessels and access them using special navigational angiography software. The treatment involves puncturing an artery in the arm or thigh, accessing the hepatic arteries with special guiding catheters, and using even thinner microcatheters (0.6-0.8 mm in diameter) to reach the arteries feeding the tumour and injecting the radioactive particles slowly with the blood stream. A precisely calculated amount of particles is “trapped” in the tumour’s microvasculature, and internal irradiation takes place – the radioactivity destroys nearby tumour cells.

Table: Different clinical scenarios for the use of SIRT in HCC that determine the usefulness of MAA analysis

SIRT procedure practices

Anterventional angiographyangiography, angiography on the screen visible at contrast-filled tumourys. It is an extremely precise and safe method that only affects the tumour without damaging other organs and tissues, but also the rest of the healthy liver. The drug, which is absorbed on the surface of the microspheres, has a much longer effect on the scarred liver tissue compared to Other treatment methods. The microspheres enter the small blood vessels of the tumour, disrupting the blood supply and leading to ischaemia and necrosis of tumour cells.

SIRT photo gallery

Radioembolisation is one of the local therapies available from 2022. included in international liver cancer treatment guides. This procedure is reimbursed in Lithuania by the Compulsory Health Insurance budget.




TERUMO's Holmium platform is the first SIRT: comprehensive platform for the treatment of inoperable liver tumours. Quiremspheres™: the only therapeutic SIRT microsphere used as part of a fully integrated platform



The occlusive balloon microcatheter from TERUMO allows redistribution of blood flow and micro-circulation, which increases the accumulation of therapeutic agents in the target lesion and reduces off-target embolization.

Untitled design


TERUMO microcatheter with integrated wire for therapeutic embolization and angiography in peripheral blood vessels. Ease of use, bend resistance, distal flexibility

Untitled design (1)


Angio-Seal™ VIP Cruciate Vein Closure Device for closure and reduction of time to haemostasis at the site of common femoral artery puncture in patients undergoing diagnostic angiography or interventional procedures

Let's get in touch

Do you have any questions or want to know more about our solutions? Write it and soon our expert will contact you.