ZH Dr Zool Hilmi

Liver-directed therapy · Malaysia

SIRT and Y-90 Radioembolisation for Liver Tumours

Selective Internal Radiation Therapy (SIRT), also called transarterial radioembolisation, is a minimally invasive treatment that delivers Yttrium-90 microspheres through the arteries supplying liver tumours.

Specialist reviewed by Dr Zool Hilmi · Updated 11 August 2026

How SIRT targets liver tumours

An interventional radiologist guides a catheter into selected hepatic arteries. The microspheres lodge mainly within the tumour microvasculature and emit beta radiation over a limited distance, concentrating treatment within the liver.

SIRT is not suitable for every liver tumour. Decisions depend on tumour type and distribution, liver function, vascular anatomy, previous treatment, general health and multidisciplinary review.

The two-stage pathway

  • Planning angiography to map the liver arteries.
  • Technetium-99m MAA administration to simulate microsphere distribution.
  • Nuclear medicine imaging to assess lung shunt and unintended extrahepatic activity.
  • Personalised activity planning and safety review.
  • Y-90 microsphere delivery followed by imaging and clinical follow-up.

Conditions that may be considered

  • Selected hepatocellular carcinoma.
  • Selected intrahepatic cholangiocarcinoma.
  • Selected colorectal cancer metastases involving the liver.
  • Other liver-dominant metastatic tumours in carefully selected cases.

Expected effects and important risks

Many patients experience fatigue, nausea, reduced appetite, abdominal discomfort or a low-grade fever after treatment. These are often described collectively as post-radioembolisation symptoms.

Rare but serious complications can occur if radiation affects non-target tissues or if liver reserve is limited. Careful mapping, dosimetry and multidisciplinary selection are therefore essential.

Frequently asked questions

Questions patients often ask

Is SIRT the same as external-beam radiotherapy?

No. SIRT delivers radioactive microspheres through the hepatic arterial circulation, whereas external-beam radiotherapy is delivered from a machine outside the body.

Why is MAA mapping performed?

The planning angiogram and technetium-99m MAA study estimate distribution and lung shunting and help identify unintended flow to organs outside the liver before treatment.

Which cancers may be considered?

Depending on multidisciplinary assessment and local indications, SIRT may be considered for selected primary or metastatic liver-dominant tumours, including hepatocellular carcinoma, intrahepatic cholangiocarcinoma and colorectal liver metastases.

What side effects can occur?

Common effects include fatigue, abdominal discomfort, nausea, reduced appetite and a temporary fever. Important uncommon complications include liver injury, gastrointestinal ulceration, radiation pneumonitis and vascular or access-site complications.

Clinical references

This patient information was prepared with reference to authoritative clinical and professional sources.