Preparation of (99m)tc-clomiphene citrate as a novel agent for breast cancer imaging

The aim of this work was to develop a novel (99m)Tc-labelled derivative based on triphenylethylene for breast cancer imaging. (99m)Tc-Clomiphene was obtained with a radiochemical yield of 94.4% by adding (99m)Tc to 1.5 mg Clomiphene citrate in the presence of 10 μg SnCl(2) at pH 7. The optimization of the labeling yield of Clomiphene citrate, with (99m)Tc, is described. The reaction parameters that affect the labeling yield were studied to optimize the labeling conditions. Radiochemical purity of the final product has been verified by means of paper chromatography and paper electrophoresis. Ehrlich Ascites Carcinoma (EAC) as a model of breast cancer cells was injected intraperitoneally (IP) to produce ascites and intramuscularly (IM) to produce solid tumor. Biodistribution study was carried out by the injecting solution of (99m)Tc-Clomiphene in normal and tumor bearing mice. The uptake in ascites was over 12.5 % injected dose per gram tissue body weight, at 1hr after injection and above 12% in solid tumor. The T/NT value for (99m)Tc-Clomiphene complex was found to be 5.5 ± 0.4 which was higher than that of the commercially available (99m)Tc-MIBI. This data revealed the localization of tracer in tumor tissue with high percent sufficient to use (99m)Tc-Clomiphene as a promising tool for the diagnosis of breast cancer.