Selective internal radiation therapy (SIRT) with (90)Yttrium microspheres for extensive colorectal liver metastases

Background/Aims: SIRT (selective internal radiation therapy) is a new modal ity for the treatment of nonresectable liver tumors which has been reported to achieve high response rates. We report our initial experience in patien ts with extensive colorectal liver metastases. Methodology: Thirty-eight (38) patients were treated with SIRT between Febr uary 1997 and November 1998. Liver involvement was < 25% in 19 patients, 25 -50% in 9 and > 50% in 10. Patients received (90)Yttrium microspheres into the hepatic artery via an arterial port and subsequent 4-weekly cycles of h epatic artery chemotherapy with 5-fluorouracil. Results: SIRT was well tolerated and no treatment-related mortality was obs erved. Responses to SIRT as indicated by falling tumor markers and serial 3 -monthly computed tomography scans were seen in over 90% of patients. Estim ated survival at 6, 12 and 18 months was 70%, 46% and 46%, respectively, an d was principally determined by the development of extrahepatic metastases. Conclusions: SIRT is well. tolerated in patients with extensive colorectal liver metastases and achieves encouraging liver tumor responses, which are well maintained by hepatic artery chemotherapy. The modality warrants wider use and investigation.