Screening examinations, conducted regularly by a health care professional can result in the detection of cancers of the breast, colon, rectum, cervix, prostate, testis, tongue, mouth, and skin at earlier stages, when treatment is more likely to be successful. Self examinations for cancers of the breast and skin may also result in detection of tumors at earlier stages. The nine screening-accessible cancers listed above account for approximately half of all new cancer cases. By surgery, radiation, chemotherapy, hormones, and immunotherapy. Since the occurrence of cancer increases as individuals age, most cases affect adults middle-aged or older.
Cancer researchers use the word risk in different ways.
Lifetime risk refers to the probability that an individual, over the course of a lifetime, will develop cancer or die from it. In the US, men have a 1 in 2 lifetime risk of developing cancer, and for women the risk is 1 in 3. Relative risk is a measure of the strength of the relationship between risk factors and the particular cancer. It compares the risk of developing cancer in persons with a certain exposure or trait to the risk in persons who do not have this exposure or trait. For example, smokers have a 10-fold relative risk of developing lung cancer compared with nonsmokers.