CHAPTER 13 



COMPARATIVE PATHOLOGY OF 

 LYMPHOCYTIC MALIGNANCIES 



T. C. JONES and JERI A. BERG 



Malignant neoplastic disease of lymphoid cells apparently occurs in all 

 species in which these cells are recognized. These species include all verte- 

 brates, among which both mammals and birds are known to be susceptible. 

 Although a great deal of information has been accumulated relative to 

 lymphocytic malignancies in various species, no sustained effort has yet 

 been made toward the thorough investigation of the disease in any species 

 with the exception of chickens, mice, and men. Still to be acquired is the 

 most important data relative to this group of neoplastic diseases in lower 

 animals. Not yet are the data adequate for use toward understanding and 

 controlling the human disease. Intensive research in several species is 

 greatly needed on this problem because the similarities in different animals 

 point toward common or related etiologic factors, in spite of the complex 

 and confusing nomenclature in present use which tends to obscure this 

 important possibility. 



Present concepts of this disease complex appear to have started to develop 

 from the work of Virchow, who in 1845 grouped human cases of malignant 

 disease involving blood cells and introduced the term "leukamie." Similar 

 disease was soon recognized in animals by Leisering 10 who described a case 

 in a horse in 1 S. r ><S and another in a pig in 1865. Bollinger reported cases 

 in pigs and a dog in 1871, and Siedamgrotzky described cases in dogs and 

 cats in that same year. Eberth is credited with reporting the first case in a 

 mouse in 1874; Jacob recorded the first case in an elephant in 1908. At the 

 present time malignant lymphocytic disease has been recognized in all 

 domestic: and many wild species of birds and mammals. The disease is not 

 known in species below the vertebrates. 



162 



