Home
Treatments
Alpha PSMA Therapy Lutetium PSMA Therapy PRRT Actinium / Alpha PRRT I-131 MIBG Therapy Terbium-161 TARE (Radioembolisation) Radium-223 Y-90 FAPI Lu-177 FAPI Upcoming theranostics
Team Second Read Service Online Consultation PET-CT Scan Service Facility at FMRI Blog Publications Gallery
Consult Us
Liver-directed Y-90 therapy

The TARE procedure.

Transarterial Radioembolisation — also called Selective Internal Radiation Therapy (SIRT) or Y-90 radioembolisation.

A liver-directed therapy that delivers radioactive Yttrium-90 microspheres through a catheter placed in the hepatic artery. Used in unresectable hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and selected colorectal liver metastases — supported by phase 2 and phase 3 evidence and recognised in current AASLD practice guidance.

Discuss your liver imaging Get a 72-hour Second Read →
Overview

What is the TARE procedure?

Transarterial Radioembolisation (TARE) is a minimally invasive, liver-directed nuclear medicine therapy in which millions of microscopic radioactive spheres are infused into the hepatic artery via a catheter, lodging selectively in the small blood vessels feeding liver tumours and delivering targeted internal beta radiation.

The procedure exploits a physiological principle established in the liver-cancer literature: liver tumours derive nearly all of their blood supply from the hepatic artery, while normal liver tissue is largely supplied by the portal vein. This arterial-portal disparity allows microspheres infused through the hepatic artery to concentrate in the tumour while sparing healthy liver parenchyma.[1]

The radioisotope carried by the microspheres is Yttrium-90 (Y-90) — a pure beta emitter with a physical half-life of approximately 64 hours and a maximum tissue penetration of about 11 mm. The combination of localised arterial delivery, short radiation path, and rapid radioactive decay allows TARE to deliver a high tumour dose with relative sparing of adjacent normal liver, the bowel, and other organs.

TARE is also referred to in the literature as Selective Internal Radiation Therapy (SIRT) and Y-90 radioembolisation. The three terms describe the same procedure; the choice of name varies by specialty — interventional radiology often uses "TARE," nuclear medicine and oncology often use "SIRT," and the manufacturers' literature usually uses "radioembolisation."

How TARE works

Three principles, one procedure.

The mechanism of TARE combines selective arterial delivery, localised beta-radiation, and embolic effect at the microvascular level. Each contributes to the therapeutic and safety profile of the procedure.

1

Selective arterial delivery

A catheter is advanced from the femoral or radial artery into the hepatic artery, then selectively into the segmental branches supplying the tumour. Because liver tumours rely overwhelmingly on arterial blood supply, microspheres infused at this level concentrate in tumour tissue while the healthy liver — which draws most of its blood from the portal vein — is largely bypassed.

2

Internal beta radiation

Once lodged in the tumour microvasculature, the Y-90 microspheres deliver beta radiation continuously over several days. Beta particles travel a maximum of approximately 11 mm in tissue and decay completely within about two weeks, confining the radiation effect to the tumour and immediate surrounding tissue.

3

Mild embolic effect

Unlike transarterial chemoembolisation (TACE), TARE is designed for minimal ischaemic effect. The microspheres are far smaller than conventional embolic agents and the procedure is not intended to occlude the artery. This allows TARE to be considered in patients with portal vein thrombosis, in whom TACE is generally avoided.[2]

Two regulatory-approved devices

The microspheres used in TARE.

Two Y-90 microsphere products are in clinical use globally. They differ in matrix material, sphere size, specific activity, and embolic load. The product is selected case-by-case after multidisciplinary review.

Glass microspheres

TheraSphere

Manufactured by Boston Scientific

MatrixInsoluble glass
Size~20–30 microns
Specific activityHigh activity per sphere
Embolic loadLower (fewer spheres per dose)
Pivotal trialDOSISPHERE-01 (HCC), EPOCH (CRC liver metastases)
Resin microspheres

SIR-Spheres

Manufactured by Sirtex Medical / China Grand Pharmaceutical

MatrixBiocompatible resin
Size~20–60 microns
Specific activityLower per sphere; more spheres delivered
Embolic loadHigher (more spheres per dose)
Pivotal trialsSARAH, SIRveNIB (HCC); SIRFLOX, FOXFIRE (CRC liver metastases)
Who is TARE for?

Established and selected indications.

TARE is used in liver-confined or liver-dominant malignancy where surgery is not feasible. Each indication has a different evidence base; eligibility is assessed in a multidisciplinary tumour board taking into account liver function, tumour distribution, vascular anatomy, and prior treatment.

Primary indication

Unresectable hepatocellular carcinoma (HCC)

The most established indication for TARE. The 2023 AASLD Practice Guidance recognises TARE as an established acceptable treatment for solitary unresectable HCC, and as an alternative to chemoembolisation for BCLC Stage B disease (Level 3, Strong Recommendation).[3] Radiation segmentectomy — selective high-dose TARE to a small liver segment — is also recognised as an alternative to thermal ablation for selected BCLC Stage A patients not suitable for surgery.

Established indication

Intrahepatic cholangiocarcinoma

TARE is used in unresectable intrahepatic cholangiocarcinoma, typically in combination with systemic chemotherapy. The evidence base is largely from prospective observational studies rather than large randomised trials, but published series have demonstrated radiological response and improvement in survival outcomes over historical controls in selected patients with adequate liver function.

Phase 3 evidence

Colorectal liver metastases (second-line)

In patients with colorectal liver metastases who have progressed on first-line chemotherapy, the phase 3 EPOCH trial (n=428) demonstrated that adding TARE to second-line chemotherapy significantly improved progression-free survival (8.0 vs 7.2 months, HR 0.69, P=0.0013) and hepatic progression-free survival (9.1 vs 7.2 months, HR 0.59, P<0.0001), although overall survival did not differ significantly.[4]

Selected use

Neuroendocrine tumour (NET) liver metastases

In patients with liver-dominant NET metastatic disease, TARE is sometimes used in selected cases, often as an adjunct or alternative to peptide receptor radionuclide therapy (PRRT). Selection is individualised. TPPL also offers Lu-177 DOTATATE PRRT for somatostatin-receptor-positive NETs, which is more typically the first-line nuclear medicine option for advanced NET disease.

Peer-reviewed evidence

What the clinical trials show.

The three citations below are the most clinically important data points underpinning current TARE practice. Each is published in a peer-reviewed journal and linked to its PubMed record at the end of this page.

Phase 2 RCT 2021
DOSISPHERE-01 · NCT02582034

Personalised dosimetry approximately doubles overall survival in locally advanced HCC.

Garin E, Tselikas L, Guiu B, et al. Personalised versus standard dosimetry approach of selective internal radiation therapy in patients with locally advanced hepatocellular carcinoma (DOSISPHERE-01): a randomised, multicentre, open-label phase 2 trial. Lancet Gastroenterol Hepatol 2021;6(1):17–29. Long-term update: J Nucl Med 2024;65(2):264–269.

Median overall survival: 26.6 months with personalised dosimetry (≥205 Gy to index lesion) versus 10.7 months with standard dosimetry (120±20 Gy to perfused lobe) — hazard ratio 0.42, P=0.0096.
Objective response rate at 3 months: 71.4% (personalised) vs 35.7% (standard), P=0.0074.
Portal vein thrombosis subgroup: 23 months vs 9.5 months overall survival.
Progression-free survival: 6.0 months vs 3.4 months.
Reference 5 — full citation →
Phase 3 RCT 2021
EPOCH · NCT01483027

The first positive phase 3 SIRT trial — TARE plus chemotherapy delays disease progression in colorectal liver metastases.

Mulcahy MF, Mahvash A, Pracht M, et al. Radioembolization With Chemotherapy for Colorectal Liver Metastases: A Randomized, Open-Label, International, Multicenter, Phase III Trial. J Clin Oncol 2021;39(35):3897–3907. Trial size: 428 patients.

Progression-free survival: 8.0 months (TARE + chemotherapy) vs 7.2 months (chemotherapy alone) — hazard ratio 0.69, one-sided P=0.0013.
Hepatic progression-free survival: 9.1 months vs 7.2 months — hazard ratio 0.59, one-sided P<0.0001.
Overall survival: No significant difference between groups.
The investigators noted EPOCH as the first positive phase 3 study of arterial radiotherapy in any disease setting.
Reference 4 — full citation →
Practice guidance 2023
AASLD · Hepatology 2023

Where current US practice guidance positions TARE in the HCC treatment algorithm.

Singal AG, Llovet JM, Yarchoan M, et al. AASLD Practice Guidance on prevention, diagnosis, and treatment of hepatocellular carcinoma. Hepatology 2023;78(6):1922–1965.

BCLC Stage A unresectable: "Targeted radioembolisation (radiation segmentectomy) or EBRT may be used as alternative therapies to thermal ablation for patients with BCLC stage A HCC who are not candidates for surgical resection, including those with tumours >3 cm in size." (Level 3, Strong Recommendation)
BCLC Stage B: "AASLD advises radioembolisation as an alternative therapy to chemoembolisation in patients with BCLC Stage B HCC." (Level 3, Strong Recommendation)
Technique: "Transarterial therapies should be performed in a selective/segmental fashion (over lobar treatment) whenever possible given a lower risk of hepatic dysfunction." (Level 5, Strong Recommendation)
Reference 3 — full citation →
The TPPL team

The physicians who deliver TARE at FMRI.

TARE at Theranostic Physicians is delivered as a multidisciplinary procedure. Nuclear medicine handles dosimetry, MAA mapping, and radiation safety; interventional radiology performs the arterial catheterisation; the multidisciplinary tumour board approves each case. The three physicians below lead the nuclear medicine side of the programme.

Director · Programme Lead

Dr. Ishita B. Sen

MBBS, DRM, DNB (Nuclear Medicine)

Director and Head of Nuclear Medicine at FMRI Gurugram. Approves TARE cases at the multidisciplinary tumour board and oversees the dosimetry and post-treatment imaging programme. President of ANMPI.

View profile → Senior Consultant · Imaging

Dr. Dharmender Malik

MBBS, DNB, MNAMS, FANMB

Senior Consultant Nuclear Medicine Physician. Leads the pre-treatment Tc-99m MAA mapping work-up and post-treatment Y-90 PET/CT or SPECT/CT verification imaging. First author of TPPL's foundational publication on radioligand therapy in prostate cancer.

View profile → Clinical Research · Dosimetry

Dr. Parul Thakral

PhD (AIIMS New Delhi)

Clinical research and dosimetry lead. PhD from AIIMS New Delhi in radionuclide therapy and personalised dosimetry — directly relevant to the personalised-dosimetry approach validated by DOSISPHERE-01. Manages quality assurance for radiopharmaceutical preparation and administration.

View profile →
Common patient question

TACE vs TARE — what's the difference?

Both procedures use the hepatic artery to deliver treatment directly to liver tumours, but they work by different mechanisms and have different roles in current practice.

Dimension
TACE — Transarterial Chemoembolisation
TARE — Transarterial Radioembolisation
Mechanism
Chemotherapy + embolic agent delivered to tumour-feeding artery; ischaemic effect plus cytotoxic effect.
Radioactive Y-90 microspheres lodge in tumour microvasculature; targeted internal beta-radiation. Minimal embolic effect.
Primary effect
Tumour ischaemia + concentrated local chemotherapy.
Localised radiation dose to tumour tissue.
Sessions typically required
Usually 2–4 sessions (repeated as imaging response dictates).
Often a single session per treated lobe; staged for bilobar disease.
Portal vein thrombosis
Generally contraindicated (risk of hepatic ischaemia).
Considered in selected cases; DOSISPHERE-01 PVT subgroup showed survival benefit.[5]
AASLD 2023 position for BCLC-B HCC
First-line (Level 1, Strong Recommendation).
Alternative to TACE (Level 3, Strong Recommendation).[3]
Hospital stay
1–2 days typical; post-embolisation syndrome common.
1 day typical; lower incidence of severe post-embolisation syndrome.
From referral to follow-up

The five phases of a TARE programme.

A complete TARE episode involves more than the treatment day itself. The work-up and follow-up phases are clinically critical and built into every patient pathway at FMRI.

1
Phase 1

Referral and work-up

Multi-phase contrast CT or MRI of the liver, dynamic vascular imaging, complete liver function panel (bilirubin, albumin, INR), tumour markers, performance status, prior treatment history, and a full review of histopathology. The case is presented to the multidisciplinary tumour board, where surgical, interventional, medical oncology, and nuclear medicine inputs combine to assess eligibility and select the treatment approach.

2
Phase 2

Mapping angiography and Tc-99m MAA scan

A separate procedure performed in advance of treatment. The interventional radiologist performs a diagnostic hepatic angiogram, identifies the tumour-feeding vessels, and may perform prophylactic embolisation of extra-hepatic arteries (e.g., gastroduodenal or right gastric arteries) to prevent non-target radiation exposure. Technetium-99m macroaggregated albumin (Tc-99m MAA) is injected and imaged via SPECT/CT to calculate the lung shunt fraction and confirm safe delivery. If lung shunt fraction exceeds 20% (or the lung absorbed dose exceeds protocol-specific thresholds), TARE may be modified or contraindicated.

3
Phase 3

Dose calculation and treatment day

Y-90 activity is calculated using either body-surface area methods (resin microspheres) or partition/personalised dosimetry (glass microspheres — the approach validated in DOSISPHERE-01).[5] On treatment day the patient is admitted, arterial access is established, the catheter is repositioned to the planned target vessel, and the Y-90 microspheres are infused under fluoroscopic guidance. The infusion itself typically takes 30 to 60 minutes; the complete treatment session is approximately 4 to 6 hours.

4
Phase 4

Post-treatment verification imaging

A Y-90 bremsstrahlung SPECT/CT or Y-90 PET/CT is acquired within 24 hours to confirm microsphere distribution and verify that the delivered dose matched the treatment plan. Most patients are discharged within 24 hours. Radiation safety counselling is provided per AERB (Atomic Energy Regulatory Board India) guidance.

5
Phase 5

Response assessment and follow-up

First imaging response assessment is typically performed at 4–8 weeks with multi-phase contrast CT or MRI, repeated at 3 months. Response is evaluated using mRECIST or EASL criteria for HCC. Liver function and tumour markers are tracked. Additional treatment cycles, contralateral lobe treatment for bilobar disease, or transition to systemic therapy is decided based on the response and overall clinical course.

Safety profile

Side effects, complications, and what to monitor.

TARE has a generally favourable safety profile compared with systemic therapy, but every patient must understand the risks. The list below distinguishes common, expected effects from rare but serious complications.

Common — usually self-limiting

Fatigue — most patients report 1–3 weeks of post-treatment tiredness
Mild abdominal discomfort in the right upper quadrant for several days
Low-grade fever in the first 1–2 weeks
Nausea, sometimes vomiting, especially in the first 48 hours
Transient elevation of liver enzymes on follow-up bloodwork
Loss of appetite for 1–2 weeks post-procedure

Less common — requires vigilance

Radioembolisation-induced liver disease (REILD) — a form of hepatic veno-occlusive disease that can be serious; more common in cirrhotic livers or in patients with prior/subsequent chemotherapy. AASLD specifically recommends selective/segmental treatment over lobar treatment to reduce this risk.[6]
Radiation gastritis or duodenal ulceration — from non-target microsphere deposition. Mitigated by careful pre-treatment mapping and prophylactic embolisation of relevant extra-hepatic arteries
Cholecystitis or pancreatitis — from non-target deposition
Radiation pneumonitis — rare; prevented by pre-treatment lung shunt fraction assessment using Tc-99m MAA
Biliary complications — biloma, cholangitis, biliary strictures, more frequent in cholangiocarcinoma patients
Frequently asked questions

Common questions about the TARE procedure.

What is the full form of TARE?

TARE stands for Transarterial Radioembolisation. The same procedure is also referred to in the literature as Selective Internal Radiation Therapy (SIRT) and Y-90 (Yttrium-90) radioembolisation. Different specialty literatures favour different acronyms — the procedure is identical.

What is the difference between TACE and TARE?

TACE (Transarterial Chemoembolisation) delivers chemotherapy plus an embolic agent through the hepatic artery to occlude tumour blood supply and concentrate chemotherapy locally.

TARE (Transarterial Radioembolisation) delivers radioactive Yttrium-90 microspheres which lodge in tumour microvasculature and deliver targeted beta radiation; the embolic effect is minimal.

AASLD 2023 guidance positions TACE as first-line for BCLC Stage B HCC and TARE as an acceptable alternative (Level 3, Strong Recommendation).[3] A detailed dimension-by-dimension comparison is on this page above.

How long does the TARE procedure take?

The Y-90 infusion itself takes approximately 30 to 60 minutes. The complete treatment day, including arterial access, selective catheterisation, infusion, and post-procedure observation, is typically 4 to 6 hours. Most patients are observed overnight and discharged within 24 hours, with radiation safety counselling per AERB guidance.

How is a patient assessed for TARE eligibility?

Eligibility for TARE depends on multiple criteria reviewed at the multidisciplinary tumour board:

Imaging: multi-phase contrast CT or MRI of the liver; vascular anatomy adequate for catheterisation. Liver function: typically bilirubin <2 mg/dL (lower thresholds for lobar treatment); adequate albumin and INR. Lung shunt fraction: confirmed safe at the pre-treatment Tc-99m MAA mapping scan. Performance status: ECOG 0–2 typically. Tumour distribution: liver-confined or liver-dominant disease. Prior treatment: review of prior locoregional or systemic therapy.

Can TARE be repeated?

Yes — TARE can be repeated, particularly for bilobar disease treated lobe-by-lobe in staged sessions. Repeat treatment to the same area is also possible after assessment of remaining hepatic reserve. Each subsequent treatment is preceded by repeat work-up and a new MAA mapping scan.

Is TARE safer than TACE in patients with portal vein thrombosis?

TACE is generally contraindicated in patients with portal vein thrombosis (PVT) because of the risk of hepatic ischaemia from disrupting the remaining blood supply. TARE has a minimal embolic effect and has been used in selected PVT patients. The DOSISPHERE-01 trial's PVT subgroup showed 23 months versus 9.5 months median overall survival with personalised vs. standard dosimetry, supporting the role of carefully dosed TARE in this clinical scenario.[5]

What is radiation safety after the procedure?

Yttrium-90 is a pure beta emitter — beta particles do not penetrate the body, so external radiation exposure from a TARE patient to family and bystanders is minimal. The Atomic Energy Regulatory Board (AERB) of India sets the regulatory framework for post-procedure precautions, including counselling on close contact, sanitation, and discharge timing. Most patients have no significant restrictions after 24 hours.

What does response assessment after TARE look like?

The first imaging response assessment is typically at 4–8 weeks with multi-phase contrast CT or MRI, repeated at 3 months. Response is evaluated using mRECIST or EASL criteria for HCC. Tumour markers and liver function are tracked in parallel. Additional treatment cycles, contralateral lobe treatment, or transition to systemic therapy is decided based on response and overall clinical course.

Speak to the TPPL team

Considering TARE for a liver tumour?

Send your recent liver imaging and pathology — we will route it to Dr. Sen's clinical workflow at FMRI and review eligibility before any in-person conversation. International patient coordination is handled directly by our concierge programme.

Open consult enquiry Send imaging for 72-hour Second Read → About Dr. Sen →
References

Sources cited on this page.

Every clinical claim on this page is sourced from a peer-reviewed publication or recognised society guidance document. Links open the PubMed record or the publisher page.

  1. 1
    Breedis C, Young G. The blood supply of neoplasms in the liver. American Journal of Pathology 1954;30(5):969–977. The original anatomical description establishing that liver tumours derive their blood supply predominantly from the hepatic artery — the physiological basis for all hepatic arterial therapies including TACE and TARE.
    PubMed Central · PMC1942590 →
  2. 2
    AASLD Liver Fellow Network. Hepatocellular Carcinoma Locoregional Therapies. Clinical Pearls series. American Association for the Study of Liver Diseases.
    aasld.org · Clinical Pearls →
  3. 3
    Singal AG, Llovet JM, Yarchoan M, et al. AASLD Practice Guidance on prevention, diagnosis, and treatment of hepatocellular carcinoma. Hepatology 2023;78(6):1922–1965. Published December 2023. Definitive US practice guidance on HCC management, including the positioning of TARE in the treatment algorithm.
    PubMed Central · PMC10663390 →
  4. 4
    Mulcahy MF, Mahvash A, Pracht M, et al. Radioembolization With Chemotherapy for Colorectal Liver Metastases: A Randomized, Open-Label, International, Multicenter, Phase III Trial (EPOCH). Journal of Clinical Oncology 2021;39(35):3897–3907. Phase 3 trial of 428 patients demonstrating significant PFS and hepatic PFS benefit with TARE + chemotherapy versus chemotherapy alone in second-line colorectal liver metastases. ClinicalTrials.gov NCT01483027.
    Journal of Clinical Oncology · DOI 10.1200/JCO.21.01839 →
  5. 5
    Garin E, Tselikas L, Guiu B, et al. Personalised versus standard dosimetry approach of selective internal radiation therapy in patients with locally advanced hepatocellular carcinoma (DOSISPHERE-01): a randomised, multicentre, open-label, phase 2 trial. The Lancet Gastroenterology & Hepatology 2021;6(1):17–29. Long-term follow-up: Garin E, Tselikas L, Guiu B, et al. J Nucl Med 2024;65(2):264–269 (PMID 38212068). ClinicalTrials.gov NCT02582034.
    PubMed · 38212068 (long-term update) →
  6. 6
    Sangro B, Gil-Alzugaray B, Rodriguez J, et al. Liver disease induced by radioembolization of liver tumors: description and possible risk factors. Cancer 2008;112(7):1538–1546. Foundational description of REILD (radioembolisation-induced liver disease) — clinical features, risk factors, and prevention.
    PubMed · 18260156 →
  7. 7
    Reig M, Forner A, Rimola J, et al. BCLC strategy for prognosis prediction and treatment recommendation: The 2022 update. Journal of Hepatology 2022;76(3):681–693. Updated Barcelona Clinic Liver Cancer staging system referenced throughout AASLD guidance.
    PubMed · 34801630 →

Medical disclaimer All physicians and researchers profiled on this page hold appointments at the Department of Nuclear Medicine & Molecular Imaging, Fortis Memorial Research Institute, Gurugram. Theranostic Physicians Private Limited (TPPL) is the clinical practice entity through which they consult and treat patients. Treatment outcomes vary by individual case; clinical decisions are made on the basis of complete medical records, current imaging, and a multidisciplinary review.