600 ADVENTURES IN RADIOISOTOPE RESEARCH 



months because variations from normal behaviour are often observed 

 only after such a long time. It is different when red blood corpuscles 

 are labelled with radioactive chromate^^^^ The labeUing is far less stable 

 than in the case of "C. One-half of the chromium leaves the healthy red 

 blood corpuscles in a time of from 26 to 32 days. The labelling chromium 

 disappears even earlier from the red blood corpuscles when the life- 

 time of the erythrocytes is curtailed. This method is of widespread appli- 

 cation in the study of the life-time of erythrocytes in cancer patients. 

 It is sufficient, in this instance, to observe the patient for a few weeks. 

 Ashby's serological method has also been applied repeatedly to deter- 

 mining the life-time. In this method, the fate of normal blood corpuscles 

 of the 0-group, transfused from another organism, is traced in the circu- 

 latory system of the patient. Tracing the life-time of heterologous 

 blood corpuscles in the circulatory system of the acceptor, however, 

 may lead to erroneous results in certain conditions. 



Curtailment of the life-time of erythrocytes in cancer patients has 

 often been observed with the aid of the two methods just mention- 

 gj(i4, 15, 16, 19, 10) YoT example, the erythrocytes in a patient with 

 severe cancer, labelled with ^iCr and investigated by Keiderling^^^^, had 

 already lost half of the labelled atoms after 12 days. The studies mention- 

 ed above were all performed on severe cases. We had the opportunity 

 to study patients with cancer of the cervix, in the Gynaecological Divi- 

 sion of the Radiumhemmet in Stockholm, which is directed by Dr. Kott- 

 meier; the majority of these were exposed successfully to therapy after 

 the study and later reached a stationary condition. A study by Dal 

 Santo^^^^ indicated that in these instances there was a curtailment of the 

 life-time in about one-half of the cases studied. 



The question now arising is how the frequently observed curtailment 

 of the life-time of the red blood corpuscles comes about in the cancerous 

 organism. 



The red corpuscles may be exposed to extracorpuscular effects in the 

 cancerous organism and abnormal erythrocytes may also be developed 

 in the can oez-o us organism. Red corpuscles have repeatedly been transfer- 

 red from cancerous to normal subjects and these have not infrequently 

 indicated a prolongation of the life-time^^^' 2^' ^^>. The transfer of nor- 

 mal erythrocytes into the circulatory system of cancer patients not infre- 

 quently resulted in curtailment of the life-time of the erythrocytes. 

 Ross and Miller^-"^^^ mention that when normal blood corpuscles had 

 circulated in the system of a neoplastic organism for 7 days and then 

 been re-introduced into the normal organism they no longer exhibited 

 the behaviour of normal blood corpuscles. From these results the conclu- 

 sion can be made that blood corpuscles are subject to an injurious extra- 

 corpuscular effect in the circulatory system of patients suffering from 

 neoplasms. 



