Prostate Cancer Clinical Trials 2
In a recent U.S. study, it was determined that prostate cancer screening trials don’t have a benefit in preventing early mortality.
You’ve heard all the pleas from physicians that you have a yearly prostate exam, but in a recent study it was shown that, while these led to more diagnoses of prostate cancer, it didn’t lower the number of prostate cancer deaths. This was a seventeen year study conducted by the National Cancer Institute. This trial was designed to help provide answers regarding prostate cancer screenings’ effectiveness.
The director of the NCI, John E. Niederhuber, MD, said that we need a more effective way to detect prostate cancer during its earliest stages. He also says that we need a better method to determine what tumors will progress and what tumors will not. Many of the recent molecular studies might yield better ways to classify what men need treatment and which can be waiting watchfully. He made it a point to say that since there are no better tests, that men should continue having annual prostate checks at their physicians’ office.
There were almost 77,000 men in the trial, which was performed at ten centers across the United States. In this group, about 38,000 were assigned to PSA screening tests for six rounds of the test, and digital rectal exams for the first four rounds. The other half of the men involved in the clinical trial were given regular care, but did not receive any orders in favor of, or against, annual screenings for prostate cancer.
In the group of men that had mandatory screenings, large percentages had PSA and DRE tests. Men in the usual-care-only part of the study had tests as well, but they were not told to have them, or not to have them. Men in the screening group of the study were sent to their usual physicians for testing as a follow-up to any PSA levels above 4, or if a DRE found something abnormal.
At seven years into the study, twenty-two percent more instances of prostate cancer were diagnosed in the group encouraged to have annual exams. The same excess continues to be observed in the newer data collected after ten years.
Of all the men who were involved in both groups, those who developed any prostate cancer were diagnosed with early stage two cancer. Later-stage cancer cases were similar in both groups. But using the Gleason scale, which is the standard for tumor aggressiveness assessment, men who were in the normal care group had more higher-scale cancers than did the group that was encouraged to have exams annually.
Men from both groups who developed prostate cancer at similar stages, received treatments that were similar to each other. After seven years, fifty deaths from prostate cancer were in the screening group, and 44 deaths were in the normal care group. So there was no obvious mortality benefit for the group who were all screened, as compared to the group who just had usual care.