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

BACKGROUND/AIMS: SIRT (selective internal radiation therapy) is a new modality for the treatment of nonresectable liver tumors which has been reported to achieve high response rates. We report our initial experience in patients with extensive colorectal liver metastases.

METHODOLOGY

Thirty-eight (38) patients were treated with SIRT between February 1997 and November 1998. Liver involvement was < 25% in 19 patients, 25-50% in 9 and > 50% in 10. Patients received 90Yttrium microspheres into the hepatic artery via an arterial port and subsequent 4-weekly cycles of hepatic artery chemotherapy with 5-fluorouracil.

RESULTS

SIRT was well tolerated and no treatment-related mortality was observed. Responses to SIRT as indicated by falling tumor markers and serial 3-monthly computed tomography scans were seen in over 90% of patients. Estimated survival at 6, 12 and 18 months was 70%, 46% and 46%, respectively, and 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.