The distribution of [3H]-dibromodulcitol in the central nervous system of patients with brain tumour.

The uptake of [3H]-dibromodulcitol ( [3H]-DBD) into glioblastomas, white matter and cerebrospinal fluid was studied in 10 patients. Single-tissue samples were taken from different subjects at 4, 15 and 24 hr after [3H]-DBD administration. The level of 3H-compounds in the central nervous system was similar after a single (400 mg/m2), or 3 smaller daily oral doses of 150-180 mg/m2 of [3H]-DBD. The distribution of radioactivity was uniform in the tumour, white matter and muscle. Between 3 and 15 hr after administration of DBD the concentration of radioactivity did not change significantly and was between 5 and 13 micrograms of DBD/g tissue wet wt. At the same time the level in the cerebrospinal fluid (CSF) remained between 1 and 4 micrograms/ml. Meanwhile, the average concentration of radioactivity in the plasma fell from 11 to 3 micrograms/ml. The elimination half-life of the labelled compounds from the tissues was about 1 day as judged from the limited number of non-serial data obtained 4 and 24 hr after the last dose of repeated drug administration.