Serum polychlorinated biphenyl (PCB) levels and risk of testicular germ cell tumors: a population-based case-control study in Connecticut and Massachusetts

Abstract

Background: The incidence of testicular germ cell tumors (TGCT) has continuously increased in Western countries over the last few decades. Some epidemiologic studies have reported that serum levels of endocrine disrupting polychlorinated biphenyls (PCBs) may be associated with TGCT risk, but the evidence is inconsistent.Methods: To evaluate whether serum levels of PCBs are associated with TGCT risk, we conducted a population-based case-control study of 308 TGCT cases and 323 controls, all residents of Connecticut and Massachusetts. Serum levels of 56 PCB congeners were measured using gas chromatography and unconditional logistic regression was used to evaluate associations with TGCT risk for concentrations of total PCBs, groups of PCBs categorized by functional characteristics, and individual PCB congeners.Results: There was no association between total serum levels of PCBs and risk of TGCT overall (quartile 4 (Q4) vs. quartile 1 (Q1) odds ratio (OR) and 95% confidence interval (C.I.) = 1.0 (0.6-1.9), ρ trend = 0.9). However, strong positive association was observed between total serum levels of Wolff Group 1 (potentially estrogenic) PCBs and risk of overall TGCT (Q4 vs. Q1 OR = 2.5, 95% CI = 1.3-4.7, ρ trend <0.05) as well as seminoma and non-seminoma subtypes. Wolff Group 1 PCB congeners that showed an increased risk of TGCT included: 25, 44, 49, 52, 70, 101, 174, and 201/177.Conclusion: We found an increased risk of TGCT associated with Wolff Group 1 PCBs and specific PCB congeners. Considering the continuing increase of TGCT, these associations should be replicated in larger studies.