PEACTICE OF MEDICINE AND HYGIENE 



a large percentage of cases it begins in the in- 

 ternal organs and when recognized is beyond 

 eradication. Cancer is becoming more preva- 

 lent. In New York State 7000 people die 

 annually of cancer. One in every twenty 

 deaths is from this disease. In England the 

 report of the Registrar- General shows that of 

 women over the age of thirty-five, one out of 

 every nine dies of cancer. Its manner of growth 

 and its general pathology are well in hand. It 

 has been zealously studied by Virchow, Cohn- 

 heim, Lebert, Waldeyer, His, Remak and 

 many others. But its treatment has not kept 

 pace with the treatment of the other diseases. 

 A new era in cancer research was opened 

 by the discovery that the disease is prevalent in 

 animals, and that it can be transplanted from 

 one to another. This makes available the ex- 

 perimental method. The animals found to 

 have cancer which can thus be experimented 

 with are dogs, rats and mice. Hanan 

 in Germany, Morean in France, Loeb in Amer- 

 ica, and Jensen in Denmark were the pioneers 

 in this study (1901-1902). Thousands of 

 these animals are now being observed by the 

 exact methods of the laboratory. An immense 

 amount of research concerning this disease is 



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