Y90 radioembolization is a minimally invasive, targeted internal radiation therapy for liver tumors. It delivers radioactive treatment directly to cancerous cells within the liver.
How Y90 Radioembolization Works
Y90 radioembolization involves the precise delivery of microscopic spheres containing Yttrium-90 (Y90), a radioactive isotope. These tiny beads, made of glass or resin, are injected into blood vessels supplying liver tumors, primarily via the hepatic artery. Liver tumors receive most of their blood supply from the hepatic artery, while healthy liver tissue is mainly fed by the portal vein. This difference in blood supply allows the Y90 microspheres to preferentially accumulate within the tumor.
Once lodged in the tumor’s microvasculature, Y90 microspheres emit localized beta radiation. This radiation travels a short distance (typically 2.5 millimeters), directly targeting cancer cells while minimizing exposure to healthy liver tissue. The Y90 isotope has a half-life of 64.04 hours, meaning 94% of its radiation is delivered within approximately 11 days. Beyond radiation, the microspheres also exert an embolic effect, blocking the tumor’s blood supply and depriving cancer cells of essential nutrients and oxygen. This dual action enhances treatment effectiveness.
When Y90 Radioembolization Is Used
Y90 radioembolization primarily treats liver cancers, including hepatocellular carcinoma (HCC), which originates in the liver, and metastatic colorectal cancer that has spread to the liver. It also treats other metastatic liver tumors, such as those from neuroendocrine tumors, breast cancer, and cholangiocarcinoma. This therapy is often considered for patients with unresectable liver tumors (those that cannot be surgically removed due to size, location, or number).
Patient selection includes individuals unsuitable for other treatments or awaiting a liver transplant. It can serve as a bridge to transplant by shrinking tumors and improving a patient’s eligibility for the procedure. The treatment aims to slow tumor growth, alleviate symptoms, and potentially extend life for those with localized liver disease. While not always curative, it can improve quality of life for patients with inoperable tumors.
Navigating the Treatment Process
The treatment process begins with an initial assessment and consultation, involving imaging scans (CT or MRI) and blood tests to evaluate liver condition, tumor size, and location. A crucial step is a diagnostic angiogram, or mapping procedure, which provides a detailed roadmap of the liver’s blood vessels. A catheter is inserted (usually in the groin or wrist) and guided to the hepatic artery to identify tumor-feeding vessels. This mapping determines the optimal delivery path for microspheres and ensures they do not travel to other organs.
On the day of the procedure, often performed outpatient, an interventional radiologist performs the treatment. A catheter is re-inserted into the identified blood vessel, and Y90 microspheres are injected. The infusion typically takes about an hour, and patients are usually released later the same day.
Following the procedure, patients may experience some temporary side effects, including fatigue (lasting a few weeks), mild abdominal pain, nausea, vomiting, and a low-grade fever. These symptoms are generally manageable with medication and usually subside within one to five days. Patients are advised to limit close contact for several days post-procedure due to residual radiation, though risk to others is minimal as radiation is highly localized. Follow-up appointments and imaging scans are scheduled to monitor treatment effectiveness and assess the tumor’s response. Most patients can resume their normal activities within a few days to two to three weeks.