The survey, published in the journal Cancer, indicated 74 percent of doctors said they will keep giving male patients the prostate-specific antigen to screen for prostate cancer, and 66 percent said it would take more time to explain why the screening had been dropped than just to keep giving the test.
More than half of those surveyed said not ordering a PSA puts them at risk for malpractice.
"It can be very difficult for doctors to break down the belief that all cancer screening tests are invariably good for all people all the time," study leader Dr. Craig E. Pollack of Johns Hopkins University School of Medicine said in a statement. "We now know that for many men, the benefits may be small and the harms significant."
The U.S. Preventive Services Task Force, a volunteer group that advises the government on medicine, formerly recommended not screening men age 75 and older for prostate cancer but now recommends no prostate cancer screening for any healthy men.
Treatments for prostate cancer can include the removal of the prostate, radiation or other therapies, each of which can cause serious side effects including erectile dysfunction, complete impotence, urinary incontinence or bowel damage.
Elevated PSA readings are not necessarily evidence of prostate cancer, and can lead to unnecessary prostate biopsy. Even when biopsies reveal signs of prostate cancer cells, evidence shows a large proportion will never cause harm, even if left untreated. Older men frequently die of other causes because prostate cancer often progresses slowly, Pollack said.