Development of F-18 5-fluorouracil and fluorodeoxyuridine as tracers of chemotherapeutic agents for liver cancer

In order to monitor 5-fluorouracil (5-FU) and fluorodoxyuridine (FUDR) uptake and metabolism in primary and metastatic liver tumors the authors synthesized F-18 analogues of 5-FU and FUDR for positron emission tomography studies. Preliminary biodistribution studies in three different nude mouse models bearing human hepatomas were done. The mean relative concentrations (dpm found/gm tissue/dpm administered/gm animal mass) for the drugs by tumor type were as follows (tumor/liver ratios given in parentheses): for tumor G2, 5-FU = 0.36 (0.04), FUDR = 0.40 (0.05); for tumor J5, 5-FU = 0.40 (0.08), FUDR = 1.1 (0.21); for tumor JE, 5-FU = 0.54 (0.05), FUDR = 0.50 (0.09). These agents may be useful for tracing drug distribution and kinetics after intraarterial or systemic injection before and after chemotherapy, as well as for evaluating differences in tumor uptake following perturbations designed to increase drug intake by tumor, such as administration of vasoactive drugs