TY - JOUR T1 - Biologic Dosimetry of <sup>188</sup>Re-HDD/Lipiodol Versus <sup>131</sup>I-Lipiodol Therapy in Patients with Hepatocellular Carcinoma JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 612 LP - 618 VL - 45 IS - 4 AU - Kim De Ruyck AU - Bieke Lambert AU - Klaus Bacher AU - Filip Gemmel AU - Filip De Vos AU - Anne Vral AU - Leo de Ridder AU - Rudi A. Dierckx AU - Hubert Thierens Y1 - 2004/04/01 UR - http://jnm.snmjournals.org/content/45/4/612.abstract N2 - One approach to treatment of primary hepatocellular carcinoma (HCC) is intraarterial injection of 131I-lipiodol. Although clinical results have been positive, the therapy can be improved by using 188Re instead of 131I as the radionuclide. 188Re is a high-energy β-emitter, has a shorter half-life than 131I, and has only low-intensity γ-rays in its decay. The present study compared the cytotoxic effect of the radionuclide therapy in HCC patients treated with 131I-lipiodol and 188Re-4-hexadecyl 2,2,9,9-tetramethyl-4,7-diaza-1,10-decanethiol (HDD)/lipiodol. To this end, dicentric chromosomes (DCs) were scored in metaphase spreads of peripheral blood cultures. The equivalent total-body dose was deduced from the DC yields using an in vitro dose-response curve. Methods: Twenty 131I-lipiodol treatments and 11 188Re-HDD/lipiodol treatments were performed on, respectively, 16 and 7 patients with inoperable HCC. Patients received a mean activity of 1.89 GBq of 131I-lipiodol or 3.56 GBq of 188Re-HDD/lipiodol into the liver artery by catheterization. For each patient, a blood sample was taken during the week before therapy. A blood sample was also taken 7 and 14 d after administration for the patients treated with 131I-lipiodol and 1 or 2 d after administration for the patients treated with 188Re-HDD/lipiodol. Results: The mean DC yield of 188Re-HDD/lipiodol therapy (0.087 DCs per cell) was significantly lower than that of 131I-lipiodol therapy (0.144 DCs per cell) for the administered activities. Corresponding equivalent total-body doses were 1.04 Gy for 188Re-HDD/lipiodol and 1.46 Gy for 131I-lipiodol. Data analysis showed that, in comparison with 131I-lipidol, 188Re-HDD/lipiodol yielded a smaller cytotoxic effect and a lower radiation exposure for an expected higher tumor-killing effect. Conclusion: 188Re is a valuable alternative for 131I in the treatment of HCC with radiolabeled lipiodol, and a dose escalation study for 188Re-HDD/lipiodol therapy is warranted. ER -