WHAT IS TARE / SIRT / Y-90?
A COMPLETE PATIENT INTRODUCTION
Transarterial radioembolization โ what it is, how it works, who it is for, and how it differs from other liver cancer treatments. A plain-language introduction for patients and families encountering this therapy for the first time.
analyticsAt a Glance
- check_circleTARE delivers radioactive microspheres directly into liver tumour blood vessels via a catheter โ no surgery required
- check_circleThe microspheres simultaneously block blood supply (embolization) and irradiate the tumour from inside (brachytherapy)
- check_circleUsed in HCC, liver metastases from colorectal cancer, neuroendocrine tumours, and cholangiocarcinoma
- check_circleCancerFax coordinates access to TARE at specialist interventional oncology centres in China and India
What Is Transarterial Radioembolization (TARE)?
Transarterial radioembolization (TARE) โ also marketed under the names SIRT (Selective Internal Radiation Therapy) and commonly referred to as Y-90 therapy โ is a minimally invasive interventional radiology procedure that targets liver tumours by delivering millions of tiny radioactive microspheres directly into the hepatic arteries that feed the tumour.
โTARE is not surgery and it is not external beam radiation โ it is precision internal radiotherapy delivered through the blood vessels, from inside the tumour outward.โ
The Embolization Component
When microspheres lodge in the small arterioles supplying the tumour, they physically obstruct blood flow โ depriving the tumour of oxygen and nutrients. This is the embolization effect, shared with TACE (transarterial chemoembolization).
The Radiation Component
Each microsphere is loaded with yttrium-90 (Y-90), a radioactive isotope that emits beta radiation โ high-energy electrons that travel a very short distance (average 2.5 mm in tissue) and destroy DNA in the cells immediately surrounding each microsphere. This is targeted brachytherapy delivered from within the tumour.
Why Liver Tumours Are Uniquely Targetable
Liver tumours derive approximately 80โ100% of their blood supply from the hepatic artery, while healthy liver parenchyma is primarily supplied by the portal vein. This anatomical difference allows microspheres injected into the hepatic artery to selectively reach tumour tissue while largely sparing normal liver โ the biological basis of TARE's therapeutic window.
Names and Terminology
TARE, SIRT, Y-90 therapy, and radioembolization all refer to the same class of procedure. 'SIRT' is the commercial term used by Sirtex (SIR-Spheres); 'TARE' is the preferred academic/clinical term; 'Y-90' refers to the radioisotope used. All are interchangeable in clinical discussions.
Which Liver Cancers Is TARE Used For?
TARE is applied across several liver tumour types โ as primary locoregional treatment, as bridging therapy before transplant, or as downstaging therapy to convert unresectable disease to resectable.
| Cancer Type | TARE Role | Evidence Strength | Notes |
|---|---|---|---|
| Hepatocellular carcinoma (HCC) | Primary locoregional; bridge to transplant; downstaging | Strong โ multiple RCTs and Phase III (SARAH, SIRveNIB) | Best used in intermediate-advanced HCC; BCLC B/C |
| Colorectal cancer liver metastases (CRLM) | Combination with chemotherapy; salvage 2nd/3rd line | Strong โ SIRFLOX, FOXFIRE Phase III | PFS benefit with FOLFOX + SIR-Spheres; OS in selected subgroups |
| Neuroendocrine tumour liver metastases | Symptom control; tumour volume reduction | Good โ prospective data, NETTER-2 context | Well-evidenced for functioning and non-functioning NET liver mets |
| Intrahepatic cholangiocarcinoma (iCCA) | Locoregional therapy in unresectable disease | Moderate โ phase II data | Emerging indication; active trials ongoing |
| Breast cancer liver metastases | Salvage locoregional therapy | Moderate โ retrospective and phase II data | Third-line+ in multi-drug refractory patients with hepatic-dominant disease |
TARE vs TACE โ How They Differ
TARE and TACE are both transarterial liver-directed therapies, and patients are often confused about when each is preferred. These are the key clinical differences.
TARE (Y-90 Radioembolization)
- Outpatient procedure in most casesTARE typically does not require hospital admission โ patients are discharged same day or after one night and experience relatively mild post-procedural syndrome.
- Radiation travels only 2.5 mm in tissueThe short beta-emission range of Y-90 limits radiation to the immediate tumour bed โ allowing treatment of tumours close to bile ducts and vessels that would be excluded from external beam radiation.
- Better tolerated in portal vein thrombosisTARE can be used in patients with portal vein thrombosis (tumour thrombus) โ a common HCC complication that contraindicates conventional TACE.
- Single-session treatment for large areasLobar or whole-liver TARE delivers a defined radiation dose in a single session โ suitable for treating multiple bilobar lesions simultaneously through sequential lobar treatment.
TACE (Transarterial Chemoembolization)
- More established historical evidence baseTACE has a longer clinical history and a larger body of randomised trial data โ particularly in BCLC B HCC โ where it has been the standard locoregional treatment for over 20 years.
- Delivers chemotherapy as well as embolizationConventional TACE (cTACE) adds a chemotherapy agent (doxorubicin, cisplatin, or mitomycin C) โ providing dual-mechanism tumour kill. DEB-TACE provides controlled drug release from embolizing beads.
- No radiation safety concerns for staff or contactsTACE uses no radioactive material โ no special radiation precautions needed after the procedure, making in-hospital logistics simpler.
- More widely available globallyTACE infrastructure is available at a broader range of interventional radiology centres internationally โ TARE requires a nuclear medicine unit and Y-90 supply chain in addition to IR capability.
TARE / Y-90 โ Key Numbers
The most important quantitative reference points for patients considering radioembolization.
- ~2.5 mmAverage tissue penetration depth of Y-90 beta radiationThis very short range is the biological basis for TARE's selectivity โ radiation is deposited almost entirely within the tumour without reaching adjacent normal structures.
- 64.1 hrsPhysical half-life of yttrium-90Y-90 decays to stable zirconium-90 over approximately 11 days (5 half-lives), after which no clinically relevant radioactivity remains.
- ~80โ100%Proportion of liver tumour blood supply derived from the hepatic arteryThe anatomical basis for TARE's selectivity โ healthy liver is primarily portal-vein supplied and largely spared.
Explore the Complete TARE / Y-90 Resource Library
Deep-dive guides covering every aspect of Y-90 radioembolization โ physics, platforms, workup, dosimetry, and clinical evidence.
Frequently Asked Questions About TARE / Y-90
Is TARE the same as SIRT?
Yes. TARE (Transarterial Radioembolization) and SIRT (Selective Internal Radiation Therapy) are two names for the same class of procedure. SIRT is the proprietary term associated with the SIR-Spheres product marketed by Sirtex Medical. TheraSphere (BTG/Boston Scientific) uses the term TARE or Y-90 radioembolization. In clinical and academic literature, TARE is increasingly the preferred neutral term that does not favour either commercial product.
Is TARE a surgical procedure? Will I be put under general anaesthesia?
TARE is not surgery. It is an interventional radiology procedure performed via a small puncture in the femoral or radial artery (in the groin or wrist) through which a catheter is threaded under X-ray guidance to the hepatic arteries supplying the tumour. Most TARE procedures are performed under conscious sedation (light sedation + local anaesthesia) rather than general anaesthesia. The procedure typically takes 1โ2 hours and patients are usually discharged the same day or after a single overnight stay.
If Y-90 is radioactive, is it dangerous to my family after treatment?
Y-90 is a pure beta emitter โ it emits high-energy electrons, not gamma rays. Beta particles have very low tissue penetration and are entirely absorbed within the patient's body, so they do not pose a radiation hazard to people in contact with the treated patient. Very small amounts of bremsstrahlung radiation (secondary X-rays generated when beta particles decelerate) are emitted, but at levels that do not require isolation. Most centres advise simple precautions โ such as avoiding prolonged close contact with pregnant women and young children for a few days โ but hospitalisation in a shielded room is not required.
Can TARE be repeated if the tumour grows back?
Yes. TARE can be repeated in selected patients where residual untreated liver is sufficient to tolerate additional radiation dose and the tumour pattern remains amenable to transarterial targeting. Repeat TARE to previously untreated liver segments, or to tumours that progressed outside the initially treated territory, is clinically practised at specialist centres. The decision to repeat requires detailed dosimetry planning and liver function assessment by the treating interventional oncology team.
How CancerFax Helps
CancerFax is a specialist cancer access and patient-navigation platform. We help patients and families understand their options, organise medical records, coordinate hospital communication, and support cross-border treatment planning where appropriate.
We help collect and organise reports, scans, pathology, biomarker results, and treatment history for structured case review.
We communicate with hospitals or trial teams to assess whether a case may be suitable for further screening.
We support appointment coordination, document submission, translation, and direct communication with international departments.
For international patients, we help with practical coordination โ travel planning, hospital admission guidance, and local support.
If this option is not suitable, we help explore other relevant treatments, clinical trials, or advanced care pathways.
From inquiry through to follow-up, our coordinators provide a single point of contact for the family.
CancerFax does not guarantee treatment access, eligibility, or clinical outcome. Our role is to help patients access accurate information, structured review, and appropriate specialist pathways.
Is Y-90 Radioembolization an Option for Your Liver Cancer?
CancerFax reviews your liver tumour records โ imaging, liver function, portal vein status, and prior treatment history โ to assess TARE eligibility and coordinates access at specialist interventional oncology centres.
This content is for informational purposes only and does not constitute medical advice. Always consult a qualified oncologist and interventional radiologist before making treatment decisions.