Document nNQgZdk39eXpq2K4aNxK7q3w6

.t ... .. '.. S E C O N D E D I T I O N 'i In collaboration with 184 conkbuton LEA & FEBIGER 1982 PHILADELPHI.\ c- - . _. _- c f 1 i 1 Acute Myelocytic Leukemia .i . ROSE RUTH ELLISON .. I i .4cutc mycioqtic leukemia (MIL) is a hetero- igeneous hiscase or p u p of diseases occurring .primarily in adults, characterized by replace- :ment of normal marrow elemems by immature -cells of tne myeloid series. Whether this a p ! c o d i t y in ditferentiation results from an 1 ImManceof inhi'oitoryand stimulatory factors ia d is potcnridly reversible or whether it r e p :cats sn iiltrinsic and irreversible malignancy Iof thcse cells independent of their ability to If -DXXIX~~S- still u-nset-tled. i _- - IEt; ol~ g ] 1 A num`kr of factors-havebeen incriminated in the caurstion of acute and chronic nyeioqTic Icukernia (CI\.IL).'aThese include x-irradiiticn. tyiosure to certain dacmicals, genetic and congenital factors, and perhaps virai infec- tions. . Raciiaxion Exposure. Acute Ieuhmia (predominantly but not exclusively myeloc+c) and chronic myelocytic leukemia (CML) hare been known to follow radiation esposure. Radiologists, prior to the development of z~odernsafety techniques, had an increased incicience of myeloc_Vrc leukemia. A dose- dqtndent increased frequency of acute and chronic myeloqtic leukemia tvas observed in ~stientswith ankylosing spondylitis treated with radiotherapy. T h e most striking data concerning the role X irradiation in the production of leukemia are those obtained in the survivors of the 1945 .:omit blasts at Hiroshima and Nagasaki These events were followed by an increased !:ncidcna of both CML and AML the increase zmtinued for nearly 20 ycars after exposure. Thus, in 1964 the inadence of AML for those ?e%than 1500 meters from the hypocrnter ivas 4 1 significantly greater than for individuals xho were at a greater distance. The incidence of acute leukemia occurred in a bimodal ashion, with peaks in 1951 and 1958. The dose;nduced relationshipsfor total body irradiation wggcsted a lack of leukemogenic effect at dose levels below 50 rads, but the existence of a threshold level has not been Froved An in- crescd zisk for males over females was seen. A retrozpeaive study concluded that ap- prcximately 5% o f d l A'IL and CZAL were possibly induced by therapeuticradiation. with doses of the same order as'those leading to leukemia in Hiroshimat and after treztment for sFondylitis."; These authors did not find a relationshipbermen diagnostic irradiation and development of leukemia. Another retrospec- tive review of diagnostic radiation exrosure did indicate a significant increase in M I L and CiVL for men @ut not in with the increased rizic re!ated to the numter of films taken; the risks in men were greater for those who had diagnostic radiation of the mrk. There was no increase in acute lymphocytic leukcmia. Cfiemicei Zxposure. The drugs implicated as Ieukemo~ensare all known to cause bone marrow depssion and/or aplasia. -The only cmmmund with an uneauivocal rdationshio to a s s t i c anemia, other q~openxasm, yelohbro: sis. or m d o i d merapias-ia. ,Uther putative leukemogens includ phenyl&tazor,e," and perhaps arsenicals, sul- fonamides. and various insecticides. Treatment'of multiple myeloma with phen- ylalanine mustard or qclophosphamide with or without irradiationhas been follo\ved by the occurrence of AUL,109J93although this complication has been seen rarely without history of exposure to eithcr mode of therapy. AhlL has also folIowd &onic use of alkylating agents in the treatment of other neoplastic diseases, including ovarian cancer, gastric cancer, and Hodgkin's dixass. Acute myelocytic IeQkemiahas been diag~osed1 to 20 years after initiation of treatment in Hodgkin's disease.lW It has been seen in patients who have reccived intensiveradiotherapy done or chemotherapy alone, but has been particularlv noted in uatients who received both in- . . -2- .. . -. .. 1- i- t, t - . 1.1 I. -. - *, ... . .. ..-....... j.,.._.-.-.i .