Lifetime occupational and para-occupational exposure to organic solvents and testicular germ cell tumor risk: a French case-control study-TESTIS.

BACKGROUND

Despite an incidence increase in recent decades, the etiology of testicular germ cell tumors (TGCT) remains poorly understood. The hypothesis of a two-stage development, combining initial alteration in utero followed by malignant transformation later in life, has been suggested. This study examined the association between cumulative lifetime occupational and para-occupational solvent exposure and TGCT risk.

METHODS

The French multicenter case-control study TESTIS included 454 cases and 670 controls. Participants provided information on their occupational history; participants' mothers (N = 547) provided information on their own and the father's occupational history. Solvent exposure was assessed by using the Matgéné job-exposure matrices. The influence of the parental and subject's occupational exposures over the lifetime and at different periods (i.e. fetal life/infancy; childhood; adolescence; subject's exposure) on TGCT was examined. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by using conditional logistic regression models.

RESULTS

An OR for TGCT of 1.03 (95% CI 0.59-1.79) was found for the lifetime solvent exposure. When each period was examined individually, the results showed an increased TGCT risk in adult males who were occupationally exposed to trichloroethylene (OR = 3.09; 95% CI 1.25-7.65); fuels and petroleum-based solvents (OR = 1.91; 95% CI 1.21-3.02); diesel, kerosene, and fuel oil (OR = 2.26; 95% CI 1.16-4.41); and ketones and esters (OR = 1.66; 95% CI 1.02-2.71), and suggested a positive association with solvent exposure during adolescence (OR = 1.77; 95% CI 0.95-3.31).

CONCLUSION

Overall, this study did not suggest a substantial role of cumulative lifetime solvent exposure and TGCT risk. The results showed an increased TGCT risk associated with solvent exposure during adulthood. Indirect exposure to certain solvents during adolescence might also promote TGCT development.