The next best thing to lifestyle changes is early detection to prevent cancer from becoming life threatening. Detecting a tumor while it is still in an early stage is the best predictor of long-term survival. For this reason, the ACS recommends a number of screening tests for people who do not have symptoms.
A cancer-related checkup is recommended every three years for people aged 20 to 40 and every year for people over age 40. For more information about other screening tests, see the table on Cancer Screening Recommendations.
Detecting cancer in its early stages significantly improves a patientís chances for survival. The American Cancer Society recommends that symptom-free patients undergo a number of regular screening tests. One such test, a double-contrast barium enema, is used to detect colorectal cancer. Barium, an X-ray opaque material or contrast medium, makes intestinal tumors and other defects stand out as dark spots against the brighter healthy intestinal tissue in X rays. The American Cancer Society recommends people over age 50 have a double-contrast barium enema every 5 to 10 years.
In addition to regular cancer check ups, advanced technologies may help detect certain cancers. Scientists have developed tests for the presence of certain genetic mutations. People who test positive for these genetic mutations may take preventive measures such as more frequent cancer screening examinations and dietary modification to reduce their risk. Women who test positive for a mutated breast cancer gene, such as BRCA1 or BRCA2, may choose to have a mastectomy even when no cancer is present. This eliminates most breast tissue before cancer has a chance to form.
The ability to determine a person's genetic risk for cancer years or even decades before it develops has raised a number of ethical, social, and psychological implications. Several government committees have published guidelines to prevent discrimination in hiring or firing employees who have had a genetic test or have tested positive for a particular cancer-causing gene. Families with high risk for cancer are also affected by the psychological implications of knowing which family members are at risk and which are not. In some cases, tests are available to identify people at risk for certain cancers, such as inherited forms of breast or colon cancers, but surefire preventive or treatment measures for these cancers have not been developed yet. While some people would prefer to know their risk for disease so they can make appropriate lifestyle changes, others prefer not to be hampered by this knowledge when no treatment exists for the problem.