WEDNESDAY AUGUST 6, 2008 (foodconsumer.org) -- The U.S. Preventive Services Task Force updated its 2002 recommendations to warn doctors and patients that prostate cancer screening based on testing of prostate-specific antigen or PSA does more harm than good to men age 75 or older.

The voluntary panel also said the balance between the benefits and risk of the screening for men under 75 remains unknown and urged doctors only to conduct the test in men who are expected to live more than 10 years and at high risk of prostate cancer.

The problem with the screening is that the PSA test is not a reliable tool to detect the cancer and it can result in false positive cases in which patients may suffer unnecessary biopsy or treatment even death.

Even if the prostate screening is effective, it is useless for men age 75 or older or for men who have health problems and are not expected to live 10 more years. This is because prostate cancer often grows very slowly and it would take 10 years or so for an elderly man to have a dire consequence if any. These men are more likely to die from other health problems.

The group said 29 to 44 percent of cases of prostate cancer are over-diagnosed. More than 75 percent of deaths occur in men aged 75 or older, meaning that prostate cancer screening is not justified for most men younger than 75 although men who are known to be at high risk of the disease may benefit from the procedure.

Unnecessary screening would lead to unnecessary treatment harming the patients. For instance, a recent study published in the Sept. 1 2008 issue of the International Journal of Cancer showed that prostate cancer patients who underwent radiation therapy had a high risk of a secondary cancer such as colon cancer.

A health observer affiliated with foodconsumer.org suggested that people need to know about the benefits and risks of any screening and treatments. He said easy modifications in diet and lifestyle may effectively reduce the risk of prostate cancer.