278 THE PROTEAL TREATMENT OF CANCER 



ing chemical conditions susceptible of investigation only by the 

 most delicate of biological methods. 



Fortunately, however, there are a few workers who appear to 

 have been impressed with the histological aspects of the problem, 

 although even these have for the most part considered this aspect 

 of the subject as having only subordinate interest. 



Among the earliest and most important observations that asso- 

 ciate the leucocytes with the process of immunization of animals 

 against cancer inoculation are those of Bashford, Murray and 

 Cramer, working under the auspices of the Imperial Cancer 

 Research Fund, in England. In a report published in the Pro- 

 ceedings of the Royal Society of London for 1909, dealing with 

 the general subject of resistant cancer inoculation, in mice, they 

 make the following highly interesting observations: 



"The phagocytosis of formed cellular elements plays an im- 

 portant role in inducing resistance; serum is impotent to induce 

 resistance, blood corpuscles do so. The energetic phagocytosis 

 which accompanies the spontaneous absorption of transplanted 

 tumors, and which occurs in absorption after exposure to radium, 

 speaks strongly for the conclusion that the processes are the same 

 in kind when blood or tumor cells, being absorbed, produce 

 resistence. But we are as yet unable to determine the extent to 

 which agencies directed against the tumor cells themselves may 

 assist in determining their early death in protected animals." 



At an earlier stage of the series of investigation, the role of 

 the leucocyte had been under consideration, as shown by a report 

 made by Bashford, Murray, and Bowen, in the Proceedings of 

 the Royal Society for 1906. In this report the authors say : 



"Of course the cells presenting complete degeneration are no 

 longer capable of giving rise to tumors. In fact they are rapidly 

 taken up by the phagocytes in the days immediately preceding 

 transplantation, and it might be concluded that growth was con- 

 tinued by cells which never tended to degenerate." 



Incidentally it is of interest to note that in connection with this 

 report the authors show a drawing of inoculated tumor tissues 

 undergoing degeneration, in which portions of the mass that stain 

 lightly are surrounded 'by cells with dark-staining nucleus and 

 protoplasm of a type closely similar to cells that I have observed 

 and studied in detail in a patient's blood taken from the im- 

 mediate substance of a cancerous mass. 



In continuance of the same line of observation, we find Da 

 Fano in the Fifth Scientific Report of the Imperial Cancer 

 Research Fund, issued in 1912, referring to the round cells that 

 occur in the margin of a tumor that is retrograding, and along 

 the strands of actively proliferating connective tissue. De Fano 

 suggests that the development of tumor immunity in mice is 

 coincident with the general reaction of the connective tissue 

 throughout the organism. He observed that the polynuclear leu- 



