Radioarsenic in Plasma, Urine, Normal Tissues, and Intracranial Neoplasms: Distribution and Turnover After Intravenous Injection in Man

Introduction  During the evolution of brain-tumor localization by means of positron-emitting radioactive isotopes over the past four years, a large amount of data on the behavior of inorganic arsenic in man has been accumulated.^1,2 The experimentally determined distribution and turnover of radioarsenic (As⁷⁴) in normal tissues, as well as in various intracranial neoplasms from over 100 patients studied, constitute the material of this report.

Methods 

A. Preparation and Administration of the Isotope.  As⁷⁴ is produced by deuteron bombardment of germanium powder in the cyclotron. A modification of the separation described by Green and Kafalas³ is now used to obtain carrier-free activity, largely as the trivalent arsenite. In this procedure, the irradiated germanium powder is dissolved in nitrohydrochloric acid (aqua regia) and the germanium driven off as the tetrachloride gas by heating. Hydrobromic acid is added to reduce the arsenic to the trivalent state, and the latter