According to the American Society of Clinical Oncology, there are risks associated with the screenings. These include, "over-diagnosis; screening tests may find slow-growing cancers that would not have caused any harm during a person's lifetime. As a result, some people may receive potentially harmful, painful, stressful, and/or expensive treatments that they did not need" (ASCO). I still believe that even if you do find a slow growing cancer that you should know about it and that you have it so you know for the future if something starts to change with your health you do not need to waste time with the diagnostic testing and can start treatment right away.
Another risk that the American Society of Clinical Oncology found was, "Increased testing. Doctors may run additional tests that a person may not need because of overdiagnosis and false positives. These tests can be physically invasive, costly, and cause unnecessary stress and worry" (ASCO). This was a big point which I did not realize because a lot of these screenings could include getting a biopsy or other invasive techniques. While theyy sometimes are necessary to rule out the diagnosis of cancer, the biopsy alone has potential risks.
With everything considered with the risk factors, I personally believe that these tests and screenings were made to do more good than harm. These screenings, if you choose to be proactive about them, could save your life by detecting early stages of cancer when it is at a potentially treatable stage.
American Society of Clinical Oncology. (2012). Cancer Screening. Retrieved March 04, 2016, from http://www.cancer.net/navigating-cancer-care/prevention-and-healthy-living/cancer-screening