Yttrium-90 labelled resin microspheres for treatment of primary and secondary malignant liver tumors.

Neither regional nor systemic chemotherapy significantly improve survival in the majority of patients presenting with liver metastases and their median survival is short. While the incidence of hepatocellular (HCC) is increasingly worldwide, the various treatment approaches that hve been developed to treat non-resectable HCC have had minimal or moderate impact on overall survival. SIR-Spheres (SIRS) are commercially available (90)Y-labelled resin microspheres that when selectively injected via the hepatic artery will become trapped in the tumor caplliary bed and will selectively deliver radiation to the tumor whilst sparing normal tissue. In this manuscript, the available literature on the use of SIRS in the clinic is summarized. First, available, predominantly phase I and II studies, on SIRS treatment performed in patients suffering from liver metastases as well as in patients suffering from multinodular asymptomatic unresectable HCC with a well preserved liver function have consistently reported a favourable safety profile for SIRS therapy; only a limited number of patients develop gastrointestinal ulceration or bleeding. Second, most of the studies also reported a high reponse rate to SIRS treatment resulting in increased life expectancy; median survival rates proved consistently higher when compared to historical controls. Finally, in two randomized controlled phase III trials, benefits were demonstrated for SIRS combined with chemotherapy when compared to the chemo-arm alone in patients suffering from colorectal liver metastasis. However, since these reports, novel, potentially more effective chemotherapeutics have been introduced for treating colorectal liver metastasis and the clinical value of (90)Y-Sirspheres when compared to these novel chemotherapeutics warrants confirmation and validation.