Difference in causes
Cancers are caused due to various reasons. Incidence of cancers varies depending upon the population in that region. Geographical region also differentiates the cancer causes as it might be due to exposure to solar radiation and the varying practices of diet. Of course diet factor is one of the causes but still it is complex as vitamins, fibres and other agents are involved in the food consumed. The other biological reasons are the sex hormones, increasing age and family history of cancer may affect the person. The unhealthy lifestyle practices like smoking tobacco also causes cancer. Bio chemical analyses provide additional information for epidemiological studies by identifying the people at risk. Molecular epidemiology can be used to identify the causative agents for the occurrence of cancer. The causes of cancer also determine the region of infection and moreover the type of the cancer is also determined.