Abstract

The incidence of breast cancer, testicular cancer and prostate cancer is increasing in Western societies. Concern has been expressed that human exposure to environmental xenobiotic compounds coupled with endocrine activity may play a role in these cancers, but supporting evidence for the existence of such a relationship is lacking. On the other hand, the twentieth century has seen profound changes in lifestyle, which have undoubtedly influenced the incidence of diseases. This report summarises present knowledge on the relationship between hormone-dependent cancers in humans and lifestyle determinants. Major lifestyle determinants related to reproductive cancer appear to be found in eating and reproductive behaviour. Specific determinants within these areas include caloric intake, physical activity, alcohol consumption, parity, exogenous hormone treatments, sexual activity and hygiene. Dramatic changes in eating patterns in the twentieth century with increased caloric intake in the presence of decreased physical activity, and increased alcohol intake and increased female smoking are thought to have promoted reproductive cancers. In addition, profound changes in reproductive behaviour with decreased parity, increased maternal age, increased sexual activity, wide application of various types of sex hormone therapy and contraceptive measures are thought to have contributed to increased reproductive cancer incidences. Current knowledge on determinants of reproductive cancer suggests that lifestyle determinants may play a more prominent role in determining trends in reproductive cancer incidences than exposure to environmental xenobiotic compounds acting on the endocrine. However, data on human exposure to environmental endocrine-active compounds are needed to allow an analysis of the actual risk of exposure to these compounds in relation to reproductive organ cancer.