What is Y-90 radioembolization?

The science behind Y-90 takes advantage of a quirk of liver anatomy: liver tumors get most of their blood from the hepatic artery, while healthy liver gets most of its blood from the portal vein. By delivering tiny radioactive yttrium-90 microspheres into the hepatic artery branches feeding the tumor, the radiation concentrates inside the tumor and largely spares the rest of the liver. The microspheres themselves are about the diameter of a few red blood cells, and they emit short-range radiation over a few weeks before becoming inert.

Y-90 is performed in two stages, about one to two weeks apart:

• Planning angiogram (mapping). Through a small needle access in the wrist or groin, we map the hepatic arterial anatomy, embolize any small arteries that could carry microspheres outside the liver, and inject a tracer (Tc-99m MAA) to measure the lung shunt fraction and personalize your dose.
• Treatment angiogram. One to two weeks later, the Y-90 microspheres are delivered super-selectively into the arteries feeding the tumor. The procedure is over in about 60 to 120 minutes and you go home the same day.

Hepatocellular carcinoma (HCC)

For HCC, Y-90 is used across the disease spectrum. Radiation segmentectomy — a high-dose, super-selective treatment of one or two liver segments — has shown outcomes that compare favorably to surgical resection in selected patients with very early disease. For intermediate-stage and selected advanced HCC, including some patients with portal vein invasion, Y-90 controls tumor growth and gives patients more options. And for patients on or being evaluated for the transplant list, Y-90 serves as a bridge to liver transplant — keeping tumors controlled while patients wait — or as downstaging to bring tumor burden within Milan or UNOS criteria. These decisions are made jointly with hepatology, hepatobiliary surgery, and the TGH transplant team.

Liver metastases and cholangiocarcinoma

For colorectal liver metastases (CRLM) that have progressed despite chemotherapy, Y-90 controls liver disease and in selected patients converts unresectable disease back to resectable. For neuroendocrine liver metastases, Y-90 is well-established for both tumor control and symptom relief. Selected breast, melanoma, sarcoma, and uveal-melanoma liver metastases are also candidates. For intrahepatic cholangiocarcinoma, Y-90 is one of the few effective options when surgery isn’t possible.

Radiation lobectomy

One of the most useful applications is radiation lobectomy: Y-90 is delivered to one lobe of the liver, treating the tumor inside it while simultaneously inducing growth (hypertrophy) of the opposite, future-liver-remnant lobe. By the time of surgery, the remnant has grown enough to make hepatectomy safe — and the tumor on the resected side has been controlled along the way. Used as an alternative or complement to portal vein embolization.

What the days look like

Both the mapping and treatment procedures are performed in the interventional suite under conscious sedation. You’ll arrive in the morning and go home the same day. Most patients feel a few days of mild fatigue and sometimes a low-grade fever — called post-radioembolization syndrome — that resolves in one to two weeks. Multiphase CT or MRI at 1, 3, 6, and 12 months measures tumor response. Y-90 can be repeated when needed.

Who is a good candidate?

Candidacy is decided by the multidisciplinary tumor board. Liver function (Child-Pugh, ALBI), tumor burden, vascular anatomy, prior treatments, performance status, and goals of care all factor in. Tissue diagnosis is established before treatment when not already known.

References

1. Salem R, Johnson GE, Kim E, et al. Yttrium-90 Radioembolization for the Treatment of Solitary, Unresectable HCC: The LEGACY Study. Hepatology. 2021;74(5):2342–2352.
2. Garin E, Tselikas L, Guiu B, et al; DOSISPHERE-01 Study Group. Personalised versus standard dosimetry approach of selective internal radiation therapy in patients with locally advanced hepatocellular carcinoma (DOSISPHERE-01): a multicentre, open-label, randomised, controlled, phase 2 trial. Lancet Gastroenterol Hepatol. 2021;6(1):17–29.
3. Mazzaferro V, Sposito C, Bhoori S, et al. Yttrium-90 radioembolization for intermediate-advanced hepatocellular carcinoma: a phase 2 study. Hepatology. 2013;57(5):1826–1837.
4. Wasan HS, Gibbs P, Sharma NK, et al; FOXFIRE, SIRFLOX, and FOXFIRE-Global Trial Investigators. First-line selective internal radiotherapy plus chemotherapy versus chemotherapy alone in patients with liver metastases from colorectal cancer (FOXFIRE, SIRFLOX, and FOXFIRE-Global): a combined analysis of three multicentre, randomised, phase 3 trials. Lancet Oncol. 2017;18(9):1159–1171.

Frequently asked questions

What is Y-90 radioembolization?

Y-90 radioembolization (also called TARE or SIRT) is an image-guided treatment that delivers tiny radioactive yttrium-90 microspheres directly into the arteries feeding a liver tumor. Because liver tumors get most of their blood from the hepatic artery while healthy liver gets most of its blood from the portal vein, the radiation concentrates inside the tumor and largely spares the rest of the liver. It is performed in two stages — a planning angiogram and a treatment angiogram — about one to two weeks apart.

How is Y-90 different from liver surgery or transplant?

Surgery (liver resection) and liver transplant remain the curative-intent options when patients qualify. Y-90 is non-surgical and is used when surgery is not the right answer — because tumor burden, location, or underlying liver function makes resection unsafe — or in coordination with surgery and transplant as a bridge to keep tumors controlled while patients wait for transplant, or as downstaging to bring patients within transplant criteria.

How is Y-90 different from TACE?

TACE (transarterial chemoembolization) delivers chemotherapy directly into the tumor’s arteries with embolic particles. Y-90 delivers targeted internal radiation. Both are catheter-based, image-guided liver-directed therapies; the choice between them depends on tumor type, vascular anatomy, prior treatments, liver function, and goals of care. For some patients, the two are used in sequence.

How is Y-90 different from external-beam SBRT?

SBRT delivers focused radiation from outside the body across multiple sessions. Y-90 delivers radiation from inside the tumor, in a single treatment session, by riding the tumor’s own blood supply into the lesion. Both are reasonable options for many liver tumors, with the choice made by the multidisciplinary team based on tumor location, vascular anatomy, prior treatments, and patient preference.

What is radiation lobectomy?

Radiation lobectomy is a strategy in which Y-90 is used to treat a tumor in one lobe of the liver while simultaneously inducing hypertrophy of the opposite lobe — so that the future liver remnant grows large enough for a planned hepatectomy. It can be used as an alternative or complement to portal vein embolization, with the added advantage of treating the tumor at the same time.

Why are patients referred to FIS for Y-90?

Patients are referred to Florida Interventional Specialists by medical oncologists, hepatologists, hepatobiliary surgeons, and transplant teams across Florida and beyond. The reasons include the depth of our experience with both glass (TheraSphere) and resin (SIR-Spheres) microspheres, advanced personalized dosimetry, and the integration of our care with the Tampa General Hospital cancer programs, including the Center for Liver Disease and Transplant — one of the busiest liver transplant programs in the country.