OBJECTIVETo analyze the biodistribution of (186)Re-lipiodol (RL) in patients with primary liver cancer (PLC) after hepatic arterial injection in attempt to assess the potential of RL as a radiopharmaceutical for the treatment of PLC.

METHODSRL was synthesized from (186)Rhenium and Lipiodol by a series of physical and chemical procedures. Doses of RL ranged from 1 110 MBq to 2 220 MBq per patient depending on the volume of tumor. Quantitative gamma camera imaging (ECT) and gamma counting of serum and urine were used to obtain data for dosimetry estimation. Serum tumor marker (AFP) level and shrinkage of tumor were used to evaluate the therapeutic efficacy of RL.

RESULTSIn the hepatic tumor, RL was selectively retained and radioactivity was very high throughout this study. The ratio of tumor concentration to the normal liver tissue concentration (T/NT ratio) was 10 - 14 at 48 hours after injection of RL. The main side effects of this therapy were transient fever and anorexia. No unacceptable toxicity was observed. In 100% of the patients, the therapy resulted in a significant decrease of AFP level and reduction of tumor volume.

CONCLUSIONThe biodistribution and imaging results demonstrated RL localized selectively in tumor, and that RL may be a potential internal radiopharmaceutical agent for the treatment of primary liver cancer.