After lung cancer, Colon cancer is the second foremost cause of cancer death in the United States. The risk for cancer of colon rises with age, with more than 90 percent of cases happening in people over the age of 50. However, it is significant to note that the disease has been identified in people of all age groups.
The connection between tobacco usage and lung cancer stands as a classic in health of public. Generally, smokers add to their risk of lung cancer between 5 and 10-fold and in developed countries, smoking is responsible for upwards of 80% of all cancers of lung. Making use of American data, 24% of men who smoke could expect to developing cancer in their expected life time.
Lately, the increase of tobacco usage to developing countries has caused papers describing similar patterns there. Hence, in a report from India, about two-thirds of all sufferers with lung cancer were smokers, making use of cigarettes and/or bidis, hand-rolled tobacco. In a research of 1,000,000 deaths in China, its risk was two to four times higher amongst men who smoked compared to men who did not smoke and this connection was in general consistent over both rural and urban areas.
In relation to colon cancer, the risk is increased amongst smokers, presumably because of the transport of carcinogens to the colon from inhaled or swallowed tobacco smoke. Data supporting this connection derive from a number of longitudinal studies in which groups of people are followed over several years to record the occurrence of a variety of illnesses.
Founded on data from both male and female health professionals in the USA, smoking emerges to double the risk of cancers of colon. The majority colon cancers start as polyps, precursor developments for cancer. Risk of cancer raises with polyp size and there is a dose-response association with increasing years of tobacco usage connected with larger polyps and, after 35 years of smoking, colon cancer.