Über die Verwendung von künstlichen radioaktiven Isotopen zur Erzielung von lokalisierten biologischen Strahlenwirkungen

Summary

Intratumoral injection of an artificial radioactive isotope (radiozinc), suspended in a solution of pectin:

The author has previously reported on a method, which consists in the utilization of an artificial radioactive isotope for the production oflocalized biological radiation effects, by means of intraperitoneal injections of radiozinc (Zn⁶³) suspended in a suitably prepared solution of pectin. This procedure was applied to a small number of cases of cancer of the ovaries, with severe peritoneal extension, and yielded rather interesting therapeutic effects in these particularly bad conditions. Evidently this method can be applied also to malignant fumors of cavitary organs, such as the urinary bladder etc.

The author investigated further, whether this procedure would also be suitable for interstitial radiotherapy, as previously presumed. Subcutaneous and intramuscular injections of the same suspension of radiozinc in pectin were thus performed on rabbits and were not followed by any diffusion of radioactivity outside the injected areas, as shown both by autoradiographs and controls of blood specimens with a counter. For the purpose of preliminary clinical investigation two cases of extended cancer of the uterine cervix recieved injections of 15 millicuries of radiozinc suspended in pectin within the tumor and its immediate surroundings (these cases were also submitted to the usual X-ray and radium-therapy). Specimens of blood and urine were checked with a counter and showed practically no radioactivity. Distinct fibrinous spots were observed a tew days later at the points of injection. This special form of interstitial radiotherapy will presumably gain some practical significance, as it offers the advantage that no foreign bodies have to be inserted in tissues as it is the case with radium needles and radon seeds, pectin being very well tolerated and resorbed by living tissues.