Cancer risk associated with simian virus 40 contaminated polio vaccine.

Background: The presence of SV40 in monkey cell cultures used in the preparation of the polio vaccine from 1955 through 1961 is well documented. Investigations have consistently demonstrated the oncogenic behavior of SV40 in animal models. Early epidemiologic studies were inadequate in demonstrating an increase in cancer incidence associated with contaminated vaccine. Recently, investigators have provided persuasive evidence that SV40 is present in human ependymomas, choroid plexus tumors, bone tumors, and mesotheliomas, however, the etiologic role of the virus in tumorigenesis has not been established. Materials and methods: Using data from SEER, we analyzed the incidence of brain tumors, bone tumors, and mesotheliomas from 1973-1993 and the possible relationship of these tumors with the administration of the SV40 contaminated vaccine. Results: Our analysis indicates increased rates of ependymomas (37%), osteogenic sarcomas (26%), other bone tumors (34%) and mesothelioma (90%) among those in the exposed as compared to the unexposed birth cohort. Conclusions: These data suggest that there may be an increased incidence of certain cancers among the 98 million persons exposed to contaminated polio vaccine in the U.S.; further investigations are clearly justified.