(Journal of the National Cancer Institute) -- A new study has found that Finnish men who immigrated to Sweden have a risk of testicular cancer that is comparible with that of men in Finland, suggesting that risk of testicular cancer is determined by environmental exposures early in life.

Anders Ekbom, M.D., Ph.D., of the Karolinska Hospital in Stockholm, and colleagues examined the incidence of testicular cancer among 93,172 Finnish men who immigrated to Sweden between 1969 and 1996. The researchers found that Finnish immigrants had a lower incidence of testicular cancer than the Swedish general population and that their risk of testicular cancer was comparable with that of the Finnish general population. Neither age at immigration nor duration of stay in Sweden had any effect on the risk.

"The findings are compatible with the hypothesis that lifetime risk of testicular cancer is determined early in life, possible before birth," the authors conclude.