title: Clinicopathological study of hematological disorders after Thorotrast administration in Japan.
abstract: Ten leukemia and four aplastic anemia cases were clinicopathologically studied in autopsies from patients who had been administered the contrast medium, Thorotrast, three to five decades previously. The short period from the appearance of hematological symptoms to death, the relatively low percentage of leukemic cells in the peripheral blood, the high frequency of erythroleukemia, i.e., 50% of leukemia patients, and a case of atypical megakaryocyte proliferation were revealed in leukemia patients. Leukemic cell infiltration in the spleen tended to become slight or minimal with the progress of fibrosis. As a result, the degree of spleen swelling was mild or lacking in leukemia patients who had been administered Thorotrast. On the other hand, cases such as hyperplastic or normoplastic bone marrow, an increase in immature granulocytic series or no decrease in the number of megakaryocytes were observed in aplastic anemia of Thorotrast-administered patients. It was thought that fibrosis in the bone marrow as well as in the spleen was induced by Thorotrast deposition. Thus, in hematological disorders of Thorotrast-administered patients, both leukemia and aplastic anemia cases were considered to be mainly of the atypical type, and it was speculated that the damage due to Thorotrast may affect the hemopoietic stem cell level and hemopoietic microenvironment.
authors.affiliation: Department of Pathology, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kamiyama
authors.forename: Y
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: S
authors.initials: S
authors.lastname: Hatakeyama
authors.forename: T
authors.initials: T
authors.lastname: Mori
authors.forename: H
authors.initials: H
authors.lastname: Sugiyama
mesh_terms: D000328:Adult; D000368:Aged; D000741:Anemia, Aplastic / Q000139:chemically induced / Q000473:pathology; D001853:Bone Marrow / Q000473:pathology; D003287:Contrast Media / Q000009:adverse effects*; D004812:Epidemiologic Methods; D005260:Female; D006402:Hematologic Diseases / Q000139:chemically induced* / Q000453:epidemiology / Q000473:pathology; D006801:Humans; D007564:Japan; D007938:Leukemia / Q000139:chemically induced / Q000473:pathology; D004915:Leukemia, Erythroblastic, Acute / Q000139:chemically induced / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000139:chemically induced / Q000473:pathology; D011289:Preleukemia / Q000139:chemically induced / Q000473:pathology; D013154:Spleen / Q000473:pathology; D013911:Thorium Dioxide / Q000009:adverse effects*
chemical_list: D003287:Contrast Media; D013911:Thorium Dioxide