LEUKEMIA: THE RELATIVE INCIDENCE OF ITS VARIOUS FORMS, AND THEIR RESPONSE TO RADIATION THERAPY*

WERE one resigned to the acceptance of the cause and cure of leukemia as a problem of the inscrutable future, requiring for its solution weapons not yet conceived in imagination, then the study of the cytologic features underlying its varied clinical manifestations would constitute little more than an exercise in morbid histology. If, on the other hand, one believes that an understanding of the cell types involved in leukemic change is a pre-requisite to the progressive clarification of the problem in its entirety, then detailed cytologic analysis becomes a potentially profitable undertaking. The purpose of this communication is to present a series of cases of leukemia, all of which have been subjected to the same criteria of differentia-tion, and to indicate the relative frequency of the several types of cellular involvement which have been observed. Consideration is also given to the sex and age incidence and to the degree of response of the patients ' disease to radiation therapy, but detailed presentation of clinical information and quantitative blood changes is deferred for later publication