PURPOSE: To prospectively evaluate the safety and effectiveness of hepatic intraarterial injection of yttrium 90 (Y-90) tetraazacycloclodecane tetraacetic acid (DOTA) lanreotide as a treatment for patients with progressive large-volume somatostatin receptor-positive liver metastases from neuroendocrine tumors. MATERIALS AND METHODS: The study was local ethics committee approved, and all patients gave informed consent. Twenty-three patients-(13 men, 10 women; age range, 21-69 years; median age, 57 years) with histologically proved large-volume liver metastases from neurcienclocrine cancers were treated. All patients had radiologic evidence of liver disease progression and high uptake of indium 111 (In-111) pentetreotide at scintigraphy. Selective hepatic intraarterial injection of 9'Y-DOTA-lanreotide (total of 36 treatments; median activity per dose, 1 GBq) was administered with or without embolization. Treatment cycles were performed in 8-week intervals. Clinical, biologic, and radiologic tumor responses were assessed 8-12 weeks after each treatment cycle. Objective tumor response was classified according to World Health Organization response criteria as complete regression, partial response, stable disease, or disease progression. Kaplan-Meier survival curves were used to calculate 1-year survivals. RESULTS: Partial response to treatment was achieved in three (16%) of 19 patients, and stable disease was achieved in 12 (63%). Four (21%) of 19 patients had continued disease progression. Clinical improvement was reported by 14 (61%) of the 23 patients, and a reduction in biologic marker levels was observed in nine (60%) of 15 patients. Reversible hematologic toxicity (National Cancer Institute common toxicity criteria grade > 2) occurred in three patients. The I-year survival rate was 63% (median survival time, 15 months). CONCLUSION: Hepatic intraarterial injection of Y-90-DOTA-lanreotide is a safe and effective palliative treatment for patients with progressive large-volume somatostatin receptor-positive liver metastases from neurcienclocrine tumors. (c) RSNA, 2005.