CHAPTER 16 



The Hematologic Effects of Ionizing Radiation 



Leon 0. Jacobson 



Professor of Medicine, Department of Medicine, The University of Chicago, 



Chicago; Scientific Director of the Argonne Cancer Research Hospital of the 



University of Chicago; Division of Biological and Medical Research, Argonne 



National Laboratory, Lemont, Illinois 



Introduction. Comparative effects of ionizing radiations: Single exposures to X rays — 

 Single exposures to fast neutrons — Comparison of effects produced by cyclotron fast neutrons 

 and X rays — Factors concerning coagulation following single exposures. Hematologic 

 effects of chronic total-body exposure to external radiations: Chronic exposure to X rays 

 and fast neutrons — Chronic exposure to repeated small doses of fast neutrons — Chronic 

 exposure to small daily doses of fast neutrons — Chronic exposure to gamma rays (radium) 

 — Pancytopenia induced by chronic exposure to gamma radiation. Hematologic effects 

 of exposure to externally originating radiation (radioelements) : Phosphorus (P 32 ) — 

 Sodium (Na, 2i )— Barium-Lanthanum (Ba-La 140 )— Yttrium (Y 91 )— Strontium (Sr 89 )— 

 Radium— Plutonium (Pu 239 )— Gold (Au 189 )— Gallium (Ga 72 ). Morphologic changes in 

 peripheral-blood cells produced by ionizing radiations: Direct vs. indirect effect of irradia- 

 tion on blood formation — "Stim ulation" of blood-forming tissue by radiation. Measures 

 modifying destructive effects of irradiation or affecting recovery: Prophylactic measures — 

 "Therapeutic" measures — Effects of combined prophylactic and therapeutic measures — 

 Antibody-formation studies — Comment. References. 



INTRODUCTION 



As a result of Heineke's (1903) pioneering research almost fifty years 

 ago it has been recognized that the blood-forming tissues are among the 

 most sensitive to ionizing radiations. After total-body exposure, mani- 

 festations of injury to the mammalian blood-forming tissues (such as 

 lymphopenia) may appear in the peripheral blood even in the absence of 

 demonstrable histopathologic change in the bone marrow or lymphatic 

 tissues. The reviews of Warren (1943), Warren and Whipple (1922), and 

 others (Minot and Spurling, 1924; Selling and Osgood, 1938) have 

 covered rather adequately the significant literature up to 1942. Few 

 observations have appeared in the past two decades that were not 

 recorded previously in the classic descriptions of the effects of X rays on 

 the blood and blood-forming tissues described in the earlier literature by 

 Lacassagne and Levadan (1924), Russ et at. (1919), Heineke (1904), 



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