CANCER ANAEMIA 



601 



The question of whether the curtaihiicnt of the life-time of erythrocytes 

 is attributable to an extracorpuscular effect or to their abnormal syn- 

 thesis can easily be decided by the study of animals. The erythrocytes 

 existing in the healthy organism can be labelled with ^H^ and after 

 incorporation, which proceeds for only a few days at a noticeal)le rate^ 

 the organism is inoculated with cancer cells. If the inoculation with 

 cancer cells affects the life-time of the labelled erythrocytes, it is then 

 certain that extracorpuscular agents are playing a part. Ehrenstein 



Cancer 

 inoculated 



• Cancer 

 o Control 



Fig. 3. Loss of ^*C by the haemin of red corpuscles of control mice and 

 such inoculated with ascites cancer cells 5 days following injection 



of glycine-i'iC. 



in our laboratory has injected one hundred mice, each with 1 /uc of 

 glycocoll-2-i^C, killed groups of ten mice at different times, isolated 

 20 mgm of haemin from the red corpuscles and compared the radioactivi- 

 ties of the haemin samples obtained at various times. With another 

 batch of one hundred mice the procedure was the same, except that these 

 were injected with Ehrlich carcinoma cells 5 days after the beginning 

 of the experiment. As shown in Fig. 3, the life-time of the erythrocytes 

 in the tumorous mice (tumour weight 1 — 3 gm) was lowered to about 

 one-half of the normal value. Because of the rapid disappearance of 

 haemoglobin from the circulatory system of the cancerous animal, it 

 would be expected that they would show a lowered haemoglobin content. 

 This was not the case; the cancerous animals had the same total of 

 360 mgm haemoglobin content as the controls and there was a marked 

 decrease in the haemoglobin content just before the death of the animals. 

 This result can be explained only by a compensation of the more rapid 

 decay of the blood corpuscles in the neoplastic organism by a more 

 rapid formation of erythrocytes. Figure 4, which represents the results 



