CHAPTER Xm 



Neoplasms 



This chapter is devoted to a description of the forms of Neo- 

 plasms that I have been able to find recorded as occurring in the 

 Dog. Certain forms, known to occur in other animals and in man, 

 are purposely omitted, because I have not succeeded in finding re- 

 liable data concerning their appearance in the Dog. 



Surgical Neoplasms comprise about five per cent of all diseases 

 the practitioner is called upon to treat (Froehner). In other words, 

 in every twenty dogs treated, one is afflicted with some form of 

 growth. 



We may conveniently divide conditions of Neoplasia into four 

 great groups : 



(a) 



(I) 

 Hypertrophy 



(b) Hyperplasia 



In which there is 

 excessive growtth 

 of a tissue in its 

 normal position, 

 the enlargement 

 being due to 



An increase in the 

 size of the individ- 

 ual cells. 



An increase in the 

 number of cells. 



(2) Inflammatory Neoplasms: 



(a) Simple Granulomata — ^Tumors formed of excessive 

 granulation tissue. 



(b) Infective Granulomata — Tumors produced by in- 

 flammatory reaction in consequence of specific mi- 

 croorganisms. 



(c) Strictures — In which there is diffuse overgrowth 

 of connective tissue producing structural changes 

 in the walls of canals. 



(3) Tumors Proper: 



(a) Simple Tumors — Tumors formed of tissues and 

 cells of the individual, the type of which predomin- 

 ates, and which have taken on a functionless and 

 excessive growth, and in which the power of growth 

 is indefinite. 



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