MRI screening for prostate cancer

At issue | Oct. 3 Your Health column, "Prostate PSA screenings key to cancer prevention; Test still holds value despite recent studies"

It's no surprise that there's confusion surrounding the prostate-specific antigen (PSA) blood test. Recommendations for when men should have it vary and results are often unclear.

Some doctors encourage yearly screening for men over age 50. Some advise men who are at a higher risk for prostate cancer to begin screening at age 40 or 45. Others caution against routine screening altogether.

There is, however, general agreement that men should be informed about the potential risks and benefits of PSA screening before being tested so they, with the advisement of their primary-care physician, can make an informed decision on what next step(s) to take. For example:

■ When the PSA is normal, 15 percent of men still have cancer.

■ When the PSA is abnormal, only 12 percent of men have prostate cancer.

In 2010, the American Cancer Society estimates 217,730 men in the U.S. will be diagnosed with prostate cancer and 32,050 men will die from it. Adding to the confusion surrounding prostate cancer is that, while one man in six will be diagnosed during his lifetime, many have slow-growing tumors that likely will not lead to death or require invasive treatment.

It is often difficult for urologists and radiation oncologists to determine the extent and expected behavior of this disease and whether deciding to treat the disease will help or possibly cause more worry or side effects.

Advances in diagnostic imaging are taking some of the confusion and worry away in managing this disease. By using modalities such as MRI, physicians have the opportunity to more accurately determine the severity of a prostate cancer and minimize the number of prostate biopsies a patient requires. Estimates have shown that unnecessary biopsies add nearly $2 million in costs to the health care system.

Currently, more than 1.2 million men in the U.S. undergo a prostate biopsy each year, but less than 15 percent come back positive for cancer. Without an optimal visual picture of the prostate and surrounding area, biopsy exams are essentially conducted "blindly."

Even though 12 to 30 samples are taken, lesions can still be missed and oversampling may occur. While imaging the prostate has historically been done with ultrasound, MRI offers clinicians improved image quality of the prostate gland to support better detection and localization of the area(s) of suspicion that will help pinpoint any specific regions of concern. Similar to MRI for breast cancer, prostate MRI provides for more thorough diagnostic assessment.

Similar to the more advanced breast MRI studies, radiologists interpreting prostate MRIs often use advanced image analysis software solutions to assist them in automating time-consuming manual processes. These solutions also provide radiologists with critical image processing and analysis tools for a more confident and efficient interpretation.