A study out of the University of North Carolina Medical Center in August of 2014 studied more than 27,000 patients over the age of 65 and questioned the widsom of doing routine cancer screening tests, especially if they had a limited life expectancy. They looked at screening tests for prostate, breast, colon, and cervix in a study from 2000 through 2010 and compared how often patients who had the highest mortality rates to those with the lowest. In general, those people with the highest risk of a shortened life span had fewer cancer screening tests, but the differences weren't that great.
Physicians are at risk for medical malpractice if a person gets a cancer and routine screenings aren't done. On the other hand, there's the issue of a financial conflict of interest that may lead to doing more tests than necessary. Fortunately, the United States Preventive Task Force (USPSTF) has created guidelines that seem to be reasonable, but many MDs are not following these guidelines.