We know that a family history of prostate cancer and the presence of certain genetic/genomic markers are associated with increased risk for prostate cancer in general and for some types of clinically significant prostate cancer in particular. We also know that:
- PSA testing may lead to a reduction in prostate cancer-specific mortality rates, but also leads to the unnecessary diagnosis of many cases of indolent cancer.
- Well targeted application of PSA testing may be able to minimize unnecessary biopsies and diagnosis of indolent prostate cancer.
In a new paper by Turner et al. in the journal Cancer, the authors report data from a randomized trial designed to explore whether patient counseling based on family history alone or based on family history and individual genetic risk data would affect patient attitudes to PSA testing and related factors.
The trial enrolled 700 men aged between 40 and 49 years of age who had never previously had a PSA test. (Alas, this was an entirely “white” sample group, and so this study really needs to be repeated in a comparable group of African-American males.)
Here are the basic study data:
- Patients were randomly assigned to
- Counseling based on family history alone (the FH arm) or to
- Genetic testing and counseling based on family history and the patient’s personal genetic risk score (the FH + GRS arm)
- At 3 months after counseling
- There were no significant differences in the rates of PSA testing between the two arms
- 2.1 percent in the FH arm
- 4.5 percent in the FH + GRS arm
- PSA testing rates increased significantly with given risk in the FH + GRS arm.
- There were no significant differences in the rates of PSA testing between the two arms
- Similar results were observed for
- Discussions with physicians at 3 months post-counseling
- PSA testing at 3 years post-counseling.
- Average anxiety levels decreased after individual cancer risk information was provided to the patients (P = 0.0007), with no differences between the men in the FH and the FH + GRS arms of the study.
The authors believe that this is the first randomized trial of multimarker genomic testing to report genomic targeting of cancer testing.
They also conclude that there was little evidence of concern about excess anxiety or over-use/under-use of PSA testing when multimarker genetic risk-based information was provided to individual patients.
Of course the costs associated with relevant genetic testing and counseling are significant, and some careful economic assessment would be needed before anyone could suggest that this type of genetic testing and counseling could be provided to every man in his 40s. That would be an expensive proposition, and the currently available pool of qualified genetic counselors is not very large.
Filed under: Diagnosis, Risk | Tagged: counseling, family, genetic, history, PSA, risk, score, testing |
“We also know that:
— PSA testing may lead to a reduction in prostate cancer-specific mortality rates,”
You forgot to mention: but such reduction is highly inconsistent from country to country and the trial data regarding treatments from the couple of countries showing a reduction is not fully disclosed. You also forgot to mention that PSA testing has failed to show a reduction in overall mortality anywhere.
“but also leads to the unnecessary diagnosis of many cases of indolent cancer”
Indeed. It detects lots more prostate cancers (contamination notwithstanding) but all those additional detections and subsequent treatments don’t save any additional lives.
Your ongoing biased comments about PSA screening are clear.
Dear David:
Well that’s a first … I am usually accused of being anti-PSA screening … and that is true … I am not in any way in favor of mass, population-based PSA screening. On the other hand, I am in favor of the use of PSA testing to identify risk among men with known risk factors for prostate cancer. You might like to note that I didn’t use the word “screening” once in the prior commentary.
I would also point out that I wrote (with very deliberate care) that “PSA testing may lead to a reduction in prostate cancer-specific mortality rates”, not that it does.
Dear David:
Well that’s first … I am usually accused of being anti-PSA screening … and that is true … I am not in any way in favor of mass, population-based PSA screening. On the other hand, I am in favor of the use of PSA testing to identify risk among men with known risk factors for prostate cancer. You might like to note that I didn’t use the word “screening” once in the prior commentary.
I would also point out that I wrote (with very deliberate care) that “PSA testing may lead to a reduction in prostate cancer-specific mortality rates”, not that it does.