Family History of Prostate Cancer and PSA-Based Screening

In a recent study, researchers looked into 12-year follow-up results to the Finnish Prostate Cancer Screening Trial to evaluate the relationship between prostate cancer screening and family history. Although family history is a known risk factor for developing prostate cancer, they curiously found no benefits to selectively screening men based on family history alone.

Family History in the Finnish Prostate Cancer Screening Trial

In the Finnish Prostate Cancer Screening Trial, 31,866 men were invited to participate in a prostate cancer screening program compared with 48,278 placed in a control group. Among men invited to participate in screening at 4-year intervals, 22,756 actively participated in at least one round of screening. This particular study, published October 2014 in International Journal of Cancer, focused on family history.

• 22,756 actively participated in at least one round of screening.
• 3 percent of these men reported a first-degree relative diagnosed with prostate cancer comp
• 6 percent of men with a family history of prostate cancer were diagnosed themselves
• 4 percent who reported no family history of prostate cancer, or no history at all, were diagnosed.

As expected, overall detection rates were slightly increased in men with a family history of prostate cancer. However, researchers also discovered interesting results on the timing of diagnoses and cancers diagnosed.They defined ‘interval’ diagnoses as those made less than four years after a negative PSA test or more than one year after a positive PSA test.

• Men with a family history of prostate cancer were more likely to test positive for elevated PSA levels (23.6 percent) than those without a family history (18.9 percent).
• Men with a family history were more likely to receive an interval diagnosis (3.5 percent of diagnoses) than men without a family history (2.1 percent).
• Men with a family history were most likely to be diagnosed with intermediate-grade cancer (Gleason score 7)
• Men with a family history were less likely to be diagnosed with high-grade disease (Gleason score 8 to 10) and more likely to be diagnosed with low-grade disease (Gleason score 2 to 6) than men without family history.

As researchers note, these results suggest that it would not be an effective strategy to selectively screen men based on family history. If this prostate cancer screening program targeted only men with a positive family history, 91 percent of cancers would have been missed.

 

Adding MRI to PSA-Based Prostate Cancer Screening

While some might use the results to further deter men from being screened at all, we believe that a more effective strategy would include adding prostate MRI to PSA-based screening. In another interpretation of these results, the background noise created by detection of low-grade, low-risk cancers continues to hinder prostate cancer screening. A strategy incorporating prostate MRI has potential to more successfully triage men who would benefit from biopsy.

 

Researchers investigating MRI in the detection of prostate cancer have produced positive results. These suggest that prostate MRI improves detection rates of intermediate- and high-grade cancers while reducing detection rates of innocuous disease and the number of biopsies required for diagnosis. Rather than discourage men from screening, particularly those with a known risk factor like family history, we should offer screening that produces higher cancer yields with fewer needles.