139 Childhood Exposure to Simian Virus 40 (SV40)-contaminated Poliovirus Vaccine and Risk of AIDS-associated Non-Hodgkin's Lymphoma E. A. Engels*1, L. Rodman1, M. Frisch2, J. J. Goedert1, R. J. Biggar1 1Natl Cancer Inst, Rockville, MD and 2Statens Serum Institut, Copenhagen, Denmark
Background: Persons with AIDS have increased risk for Non-Hodgkin's Lymphoma (NHL). Recent studies have reported detection of DNA sequences from SV40 in a large proportion of AIDS-associated NHLs. SV40 was present as an accidental contaminant in poliovirus vaccines used widely in the U.S. during 1955-1962.
Methods: The AIDS Cancer Match Registry study is a registry-based cohort study of cancers in persons with AIDS in 11 U.S. geographic areas (1980-1996). We used data from this study to compare NHL incidence in 2 groups with AIDS: those born in 1957-1961 (exposed to SV40-contaminated poliovirus vaccine as children, n = 39,468) and those born in 1964-1967 (born after vaccines were cleared of SV40 and thus unexposed, n = 17,340). Poisson regression was used to adjust for differences in demographic factors.
Results: Among persons with AIDS, NHL incidence was 11.7 per 1000 person-yrs in the SV40-exposed group (616 NHL cases) and 10.1 per 1000 person-yrs in the SV40-unexposed group (230 cases). This difference was borderline significant (relative risk 1.15, 95% CI, 0.99-1.34, p = 0.06). However, SV40-exposed and unexposed groups differed by race (44.4% vs 38.8% white, p < 0.0001), sex (81.3% vs 76.3% male, p < 0.0001), and age (mean age at AIDS onset, 32.0 vs 27.2 yrs, p < 0.0001). Furthermore, NHL incidence was relatively high among whites (p < 0.0001) and homosexual males (p < 0.0001) and tended to increase with age (p = 0.09). After adjusting for race, sex, age, HIV risk group, and registry area, there was no association between SV40 exposure and NHL incidence (adjusted relative risk 1.01, 95% CI, 0.82-1.24, p = 0.96). We examined risk for particular NHL subtypes in which SV40 sequences were reported in prior laboratory studies. SV40 exposure was not related to increased incidence for these subtypes, specifically for intermediate-grade (adjusted relative risk 0.93, 95% CI, 0.62-1.40) or immunoblastic (1.33, 0.75-2.37) NHLs.
Conclusion: Childhood exposure to SV40 via receipt of contaminated poliovirus vaccine was not related to risk for AIDS-associated NHL. These findings do not support a role for SV40 in lymphomagenesis, even among immunosuppressed persons.
