Cancer Risks Start Early

The risk of testicular cancer is established largely by environmental exposures early in life, a new study suggests, although the researchers admit that at this point they aren’t exactly sure what type of exposures increase the risk.

For at least 50 years, there has been an “unexplained” epidemic of testicular cancer in several populations, although there is a marked difference in the occurrence of the disease among countries Dr Anders Ekborn, of the Karolinska Hospital in Stockholm, Sweden and associates write in the Journal of the National Cancer Institute.For example, the incidence of testicular cancer is roughly twice as high in Sweden as it is in Finland and Denmanrk. “These differences cannot be explained solely by genetic differences, but environmental exposures, particularly early exposures, have been implicated in the (development) of testicular cancer,” they say.To investigate further, Ekbom’s group identified 93,172 Finnish men who emigrated to Sweden between 1969 and 1996. These immigrants were less likely to develop cancer than the Swedish general population.There was no link between age at immigration or duration of stay in Sweden and the reduced risk of testicular cancer.”The findings are compatible with the hypothesis that lifetime risk of testicular cancer is determined early in life, possibly before birth,” they say.(Source: Journal of the National Cancer Institute: The Weekend Australian, 7th September 2003)