Historical and contemporary correlates of syphilis and cancer

Background. This study examined the relationship between antecedent syphilis infection and cancer incidence in an attempt to identify specific cancer patterns. Methods. The study cohort consisted of 16 420 people diagnosed with syphilis between 1972 and 1987 and who were residents of New York State, exclusive of New York City, at time of diagnosis. Incident cancers among cohort members were identified through linkage with files maintained by the New York State Cancer Registry. Results. A total of 350 cancer cases were diagnosed among cohort members. For males and females combined, incidence was significantly elevated for cancers of the oral cavity standardized incidence ratio (SIR = 169, 95% confidence interval [CI]: 109–249), and specifically for cancer of the tongue (SIR = 251, 95% CI: 108–494). Significantly elevated incidence was observed among males for Kaposi’s sarcoma (SIR = 2000, 95% CI: 1290–2950). Conclusion. While no conclusions may be reached concerning causality, the data do argue for increased cancer surveillance among people with syphilis. Moreover, findings are discussed in light of historical considerations.