Studies examine overuse of scans in determining status of prostate cancer

During Prostate Cancer Awareness Month, researchers will publish the findings of two studies examining the use, or overuse, of scans in determining the status or level of a patient's prostate cancer after diagnosis. "Typically, patients with an elevated PSA level undergo a prostate biopsy to confirm the presence of cancer. Following the official diagnosis, the doctor must then evaluate whether the cancer is localized or if it has already spread to other areas of the body," explains Dr. David Samadi, Vice Chairman, Department of Urology, and Chief of Robotics and Minimally Invasive Surgery at The Mount Sinai Medical Center. Dr. Samadi is a robotic surgery and prostate cancer treatment expert that has completed over 3,500 successful robotic prostatectomy procedures in his New York Urology practice.  

In order to stage a prostate cancer diagnosis and determine the likelihood that the cancer will grow or spread, the Gleason grading system is used. According to Dr. Samadi, "Based on the biopsy and the differences in the prostate cell patterning from a normal prostate, a score is assigned. A Gleason score of 2-6 is considered low risk, a seven is moderate and a score of 8-10 is considered high risk – meaning the cancer is very likely to spread, if it hasn't done so already."

The American Urological Association guidelines indicate that only high-risk prostate cancer patients should go on to have bone or CT scans. Two recent studies indicate that these guidelines are not being followed and there is great inconsistency in physician usage.

A 2004-2005 study of 30,000 U.S. Medicare prostate cancer patients looked at how many men underwent CT scans relative to the level of their prostate cancer risk. Only sixty-percent of the high-risk men had bone scans, while roughly 30 percent of the low-risk and nearly 50 percent of the moderate-risk patients received scans. "As a prostate cancer specialist, I know doctors are often looking for as much information as possible. In our quest to understand everything that's going on with a patient, over-testing can occur. The guidelines should be respected, but patient care must be individualized," said Dr. Samadi. "Of course, it's troubling that a large percentage of the high-risk men with prostate cancer in this study did not have bone scans," he continued.

Scan testing guidelines intentionally limit use for two main reasons. First, the scans are very costly to the healthcare system. Second, each scan exposes the patient to a small amount of radiation that, in excess, can lead to cancer. For these reasons, the American Urological Association believes that scans are beneficial only to high-risk prostate cancer patients. To this, Dr. Samadi adds that, "in lower risk patients, the likelihood of a positive bone or CT scan is slim. For these men, the cancer is localized in the prostate."

A second study, to be published in The Journal of Urology this month, involved 150 urologists across four states. The 2009 research looked to determine the impact of increased practice awareness guidelines on the incidence of scan referrals for 858 prostate cancer patients. Initially, 31% of the patients had bone scans and 28% had CT scans. After physicians received, or were reminded of, the guidelines set forth by the American Urological Association and the National Comprehensive Cancer Network, those numbers dropped. Further, the researchers shared the results of scans ordered by physicians and their colleagues in their evaluation of prostate cancer, and the numbers dropped again. "It appears that the combination of guideline reminders and collaboration with peers is a successful formula for managing the frequency of bone and CT scans," concluded Dr. Samadi.

"Continued focus on new testing procedures and enhanced prostate cancer screening tools prior to biopsies and scans will help this issue in the future," said Dr. Samadi. "Still," Dr. Samadi adds, "the true severity of a man's prostate cancer cannot be known until it is seen first-hand during a prostatectomy."

More can be seen from prostate cancer expert, Dr. David Samadi, who is also part of the Fox News Medical A-Team.