title: Cancer incidence among Swedish patients exposed to radioactive thorotrast: a forty-year follow-up survey.
abstract: Thorotrast is an alpha-particle-emitting radiological contrast medium that caused chronic exposure to internal alpha-particle radiation when it was administered systemically. Cancer incidence in 432 Swedish patients exposed to Thorotrast was evaluated by computerized linkage of the cohort with the Swedish Cancer Register. Standardized incidence ratios (SIRs) were calculated as the ratio of observed cases in the cohort to expected cases in the general population. A total of 170 cancers occurring in 152 individuals were reported, whereas only 57 cases were expected. The SIR was significantly increased for cancer at all sites (3.0), with the largest excesses noted for primary liver and gallbladder cancer (SIR = 39.2). Other significantly elevated risks were observed for liver cancer not specified as primary, small intestine cancer, stomach cancer, leukemia, kidney cancer, CNS tumors, and pancreatic cancer. Among women, there was a significantly increased risk for lung cancer, based on a small number. Our results show that cumulative radiation exposure is directly related to carcinogenesis in the liver and gallbladder, which is consistent with earlier findings. In addition, there may be a relationship between radiation exposure and the development of other solid tumors.
authors.affiliation: Department of Medical Epidemiology, Karolinska Institutet, Stockholm, Sweden. ullakarin.nyberg@telia.com
authors.forename: Ullakarin
authors.initials: U
authors.lastname: Nyberg
authors.forename: Bo
authors.initials: B
authors.lastname: Nilsson
authors.forename: Lois B
authors.initials: LB
authors.lastname: Travis
authors.forename: Lars-Erik
authors.initials: LE
authors.lastname: Holm
authors.forename: Per
authors.initials: P
authors.lastname: Hall
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology / Q000209:etiology*; D016019:Survival Analysis; D013548:Sweden; D013911:Thorium Dioxide / Q000009:adverse effects*; D013997:Time Factors
chemical_list: D013911:Thorium Dioxide