Home About Clinicians Patients Investors Careers Media Contact Clinicians > About SIR-Spheres microspheres > Mode of Action To watch the video in a different language click on the available version below: Arabic | Dutch | French | German | Italian | Spanish | Turkish SIR-Spheres®Y-90 resin microspheres are directly targeting liver tumours via the hepatic artery minimise exposure to the remaining healthy liver tissue Due to their relatively low density of 1.1 g/mL, SIR-Spheres Y-90 resin microspheres travel with the blood stream are taken deep into the tumour microvasculature where they become lodged. SIR-Spheres Y-90 resin microspheres can therefore be delivered in a slow deliberate manner to achieve an even distribution to maximize the number of microspheres delivered, to optimize tumour coverage - even in patients with extensive disease. DOORwaY-90 Study International Recommendations FLEXdose Delivery Programme About SIRT About SIR-Spheres microspheres Mode of Action How are SIR-Spheres microspheres administered Patient Selection Potential adverse events Radiation Safety Aspects Follow Up Peri-Procedural Medications - mCRC Clinical Studies + HCC Clinical Studies + Ongoing Clinical Studies Customer Support and Training Programs Events Frequently Asked Questions Who we are Sirtex Medical is a global healthcare business with offices in the U.S., Australia, Germany and Singapore, working to improve outcomes in people with cancer. Our current lead product is a targeted radiation therapy for liver cancer called SIR-Spheres® Y-90 resin microspheres. What are SIR-Spheres® Y-90 resin microspheres? SIR-Spheres® Y-90 resin microspheres are a medical device used in Selective Internal Radiation Therapy (SIRT) for treatment of unresectable hepatocellular carcinoma (HCC) and unresectable metastatic liver tumors from primary colorectal cancer in patients refractory to or intolerant of chemotherapy. To view the Technical Bulletin regarding our indication, click here. Contact or follow us Contact Us SIR-Spheres® is a registered trademark of Sirtex SIR-Spheres Pty Ltd. Terms of Use | Privacy Information 892-EUA-1117 This content is intended for healthcare professionals only By clicking "Yes" you are confirming that you are a healthcare professional. If you are not a healthcare professional, then please click "Go to Homepage" which will direct you to the Sirtex homepage. Yes Go to Homepage Effective May 7, 2021, SIR-Spheres will have the following indication for use: SIR-Spheres Y-90 resin microspheres are indicated for the treatment of unresectable hepatocellular carcinoma (HCC) and unresectable metastatic liver tumors from primary colorectal cancer in patients refractory to or intolerant of chemotherapy. Click here to view our Technical Bulletin. Ok