ATOMIC WEAPONS AGAINST CANCER — LOCKARD 267 



far no substance with true specific localization in cancerous tissue has 

 been discovered, but the localization with radioisotopes is so much 

 greater than with the older sources of radiation, X-rays, and radiAm 

 which is dangerous to deposit internally, that the administration, 

 orally or directly into the cancerous tissue, of radioisotopes is now a 

 recognized method of radiotherapy — and in some few instances, the 

 most efficacious one. 



Today, radioiodine and radiophosphorus have been proved effective 

 in treating the noncancerous conditions of hyperthyroidism and poly- 

 cythemia (abnormality of the blood-forming tissues), respectively; 

 less effective in treating cancer of the thyroid and leukemia (cancer 

 of the blood-forming tissues), also respectively. Nor are these the 

 only elements that can be used ; therapy is also possible with radio- 

 cobalt and radiogold. 



The chief value of radiocobalt results from the fact that it resembles 

 radium, the old standby in the treatment of cancer by radiation, in 

 that it emits gamma rays; but at the same time it has several advan- 

 tageous qualities that radium lacks. One important advantage is 

 price. Whereas radium is so expensive (it costs between $15,000 and 

 $20,000 a gram) that smaller hospitals borrow it from larger ones, 

 cobalt 60 is manufactured abundantly enough for free supply to 

 cancer-research workers and for sale at a low price to paying patients. 

 Another advantage is application; while radium is contained in non- 

 pliable tubes, radiocobalt can be made up in pliable shapes. The 

 most interesting advantage is the ease with wliich radiocobalt can be 

 manufactured and stored : ordinary cobalt can be fabricated, before 

 irradiation, into cobalt wire; after irradiation it can be stored like 

 thread on a spool ; and like thread it can be snipped off in any length 

 needed. In addition, radiocobalt, if accidentally set free in the body, 

 does not lodge in the bone as radium does but is quickly excreted. It 

 can, finally, be handled more safely and with less shielding than 

 radium. 



Radiogold, like radiocobalt, has several advantages over the tradi- 

 tional types of radiation. In the first place, radiogold can be injected 

 directly into the malignant tissue; X-rays cannot. And second, be- 

 cause of a half-life of only 2.7 days, radiogold need not be removed, 

 as radium needles must. 



In order to improve therapy with radioisotopes, scientists are study- 

 ing the selective pick-up by cancerous tissues of various compounds 

 that can be synthesized with the radioisotopes of a number of ele- 

 ments. Cancer is frequent in the organs controlled by sex hormones — 

 the uterus, the breast, and the prostate gland. Since these organs de- 

 pend upon known chemical compounds, some sex hormones containing 

 radioisotopes have been synthesized. Unfortunately, so far no target 



