SYMPTOMS AND BLOOD-CHANGES 363 



We may assume that normally the majority of the lymphocytes are pro- 

 duced in the spleen and lymph-glands, and only a few in the bone-marrow. 

 As, however, hyperplasias of the spleen and lymph-glands occur without 

 lymphemia ("pseudo-leukemia"), as well as with it (lymphocyte leukemia), 

 and since, moreover, there are cases of leukemia with lymphadenoid changes 

 of the bone-marrow but without enlargement of the spleen or lymph-glands, 

 we may conclude that the implication of the lone-marroiv, i. e., the super- 

 vention of increased marrow activity in simple hyperplasia of the spleen and 

 lymph-glands, represents the most important element in the development of 

 leukemia (Neumann). However, in my opinion this does not explain why an 

 increase of the lymphocytes in the blood may not occur in hyperplasia of the 

 spleen and lymph-glands without an affection of the bone-marrow. As the 

 small lymphocytes which are formed in the lymph-glands under normal con- 

 ditions permanently enter the circulating blood, it is not apparent why, with . 

 an increased production in the lymph-glands and with a marked migration 

 into the blood, they should not appear there in greater numbers. On the 

 other hand why do we always have lymphemia when the bone-marrow is 

 implicated? The explanation that in hyperplasia of the tissue of the spleen 

 and lymph-glands their capsule also dilates, and therefore (in contrast with 

 the conditions in hyperplasia of the bone-marrow), no mechanical migration 

 of the lymph-cells into the blood occurs, is contradicted by the reflection that 

 if this were true every disturbance in the expansile power of the capsule 

 should result in a marked overflow of lymph-cells into the blood. In my 

 opinion, it is better for the present not to consider pseudo-leukemia at all 

 in connection with leukemia, and also not to look for the nature of leukemia 

 in the increase of the white blood cells alone. 



We cannot, I believe, refrain from asking what becomes of the white 

 blood cells which are so enormously increased in the organism in leukemia. 

 That in health the leukocytes are partly excreted and partly destroyed in 

 the internal parts of the body is not to be doubted. If, with the enormous 

 increase of white cells in the blood of leukemics, the consumption does not 

 go hand in hand with the increased production, a surplus of white cells in 

 the blood must result. But there is no cogent proof as yet for the view that 

 there is any such increase in the consumption of leukocytes, which in this 

 instance would have to be enormous in order to keep pace with the increased 

 production. 



My conception of the pathogenesis of leukemia is, therefore, the follow- 

 ing: The action of a specific agent causes a pathologically great stimulus to 

 the growth of the hematopoietic tissues of the hody, which especially affects 

 the production of white hlood-corpuscles. As a result of this, a flooding 

 of the Hood, at one time with lymphocytes, at another time with leukocytes, 

 with mature and immature forms of the same, occurs. This change m the 

 Mood is continued, partly ly the pathologic irritation of the blood-forming 

 organs, partly because the superfluous white blood cells are insufficiently used 

 up in the economy of the body. 



