234 SCIENCE PROGRESS 



treatment. The treatment is stated not to have succeeded in 

 the cases in which the tumour was larger than a cherry and the 

 mortality produced by it appears to have been about 70 per cent. 

 The theory of the treatment is based upon Ehrlich's statement 

 that tumour cells possess a much greater avidity for oxygen and 

 nourishment than do the cells of normal tissue. 



Quite recently Neuberg, Caspari and Lohe have published 

 the results of somewhat similar experiments. 1 These observers 

 attribute the selective action of the preparations they have used 

 to the presence in the tumour cells of certain enzymes which are 

 absent from the cells of the body tissues. They bring forward 

 in support of this view the rapid growth and the rapid degenera- 

 tion of the tumour cells. Rapid growth is a characteristic 

 feature of some strains of experimentally produced tumours in 

 mice and rats and as shown in the last number of Science 

 Progress may probably be produced in all by a process of 

 selection. Degeneration and death of the cells in the centre of 

 these tumours is probably a characteristic of all strains but it is 

 not of all kinds of malignant growths in the human subject, 

 though it is perhaps more common in some kinds than is usually 

 recognised. With regard to this point Ewing says 2 that he 

 does not consider it has yet been proved that well-developed 

 tumour tissue undergoes autolysis more rapidly than an 

 equivalent normal tissue. As evidence to the contrary he 

 quotes the experiments by himself and Beebe 3 in which dog's 

 blood was passed by artificial circulation through test tubes 

 containing fragments of sarcoma from a dog. The fragments 

 remained alive during from eight to ten days ; fragments of 

 dog's liver and kidneys became necrotic and autolysed in forty- 

 eight hours under the same conditions. 



Perhaps the most suggestive evidence with regard to the 

 existence of a specific ferment in tumour cells is provided by 

 the work of Beebe. 4 From the purified nucleoproteids of cancer, 

 he prepared a serum which agglutinated the emulsified cells of 

 cancer and precipitated the nucleoproteids derived from this 

 source but acted very feebly and only when used in large pro- 



1 " Weiteres iiber Heilversuch an Geschwulstranken Tieren mittels tumoraffiner 

 Substanzen," Berl. klin. Woch. July 22, 191 2. 



2 "Cancer Problems," Arch, of Internal Medicine, vol. i. 1908. 



3 Beebe and Ewing, Brit. Med. Jonrn. 1906, ii. 1559. 



4 Quoted by Ewing in " Cancer Problems," op. cit. 



