Intra-tumoural injection of 90Y microspheres into an animal model of hepatoma

Background Intrahepatic arterial injection of Y-90 glass microspheres (Y-90 microspheres) is a useful therapeutic modality for inoperative liver tumour. Recently, a new concept of interstitial radiotherapy in the treatment of hepatic malignancies has been carried out with even more encouraging results. However, information regarding this technique is still very rare. The purpose of this study was to analyse the kinetics and biodistribution of Y-90 microspheres in rats with hepatic tumours following intra-tumoural injection. Methods Twenty male Sprague-Dawley rats with hepatoma were killed at 1 h, 24 h, 48 h and 72 h (five rats each time) after intra-tumoural injection of approximately 7.4 MBq of Y-90 microspheres. Samples of various organs were obtained and used to calculate the tissue concentrations and radiation doses. Results Our data showed that the radioactivity in the tumour was very high throughout this study. The lung was the only organ other than the tumour which showed high radioactivity. The concentrations of radioactivity in other organs, such as normal liver, muscle, spleen, bone, testis, and whole blood were quite low throughout the study. Conclusion Direct intra-tumoural injection of Y-90 microspheres is extremely attractive as a clinical therapeutic alternative in hepatoma patients. ( (C) 2001 Lippincott Williams & Wilkins).