Genetics and inherited prostate cancer risk

Prostate Cancer: Major Genetic Risk Factor Found: “Harvard Medical School researchers have identified a DNA segment on chromosome 8 that is a major risk factor for prostate cancer, especially in African American men. The paper appears in the August electronic edition of the Proceedings of the National Academy of Sciences (also see PNAS’s
news tip below).

‘This paper identifies a genetic risk factor that about
doubles the likelihood of prostate cancer in younger African American
men,’ says principal investigator David Reich, PhD, Harvard Medical School
assistant professor of genetics with the HMS Department of Genetics and
the Broad Institute. ‘This finding may explain why younger African
Americans have an increased risk for prostate cancer than do other
populations–and may also explain why this increased risk in African
Americans attenuates with older age.’”

Source:
Medical
News Today


I came across this article today on the internet.

This reminded me about a recent discussion that I was having with one of my patients and then with a partner of mine.

Suppose you have a patient that has a strong family history of prostate cancer and a high PSA who has a biopsy. Lets also suppose that the biopsy does not show any evidence of definite prostate cancer, but has premalignant findings.

The patient asked me if I could take out his prostate. My answer was no, in that the side effects of the surgery were significant and that I did not feel any urologic oncologist would feel comfortable doing that.

Some statistics that are relevant include:
A mans lifetime risk of developing prostate cancer is about 1 in 8.
If you have a first degree relative (father, brother, son) who has prostate cancer, then you have about a 2.5 times higher chance of developing prostate cancer.
If you have a 2 first degree relatives (father, brother, son) who has prostate cancer, then you have about a 5 times higher chance of developing prostate cancer.
If your relative is under 65 years at the time of diagnosis, this gives you a higher risk.
If your brother has prostate cancer that is worse than if your dad has it.
Studies show than an identical twin has a 25% of having prostate cancer and a fraternal twin about 7%.

In the last few months, as I have performed more robotic prostatectomies and noticed more patients regaining sexual function and urinary function sooner, I am starting to reconsider my original answer.

One of my colleagues pointed out to me that women sometimes have mastectomies (removal of breasts) to prevent breast cancer if they are at a high risk genetically or have pre-malignant changes.

I wonder what peoples thoughts are on this. I wonder if other urologists had considered this or have done this.

I think my answer would still be to follow the patient closely and do frequent biopsies, but one day I think my answer will change. If there was a genetic test that concluded the patient had a 100% chance of developing prostate cancer that would change my answer to prophylactic prostatectomy.
Patient Poll
<a href=”http://polls.blogflux.com/poll-4385.html” mce_href=”http://polls.blogflux.com/poll-4385.html”>Take the poll</a></p> <p><a href=”http://polls.blogflux.com/” mce_href=”http://polls.blogflux.com/”>Free Poll by Blog Flux</a>
Urologist Poll
<a href=”http://polls.blogflux.com/poll-4386.html” mce_href=”http://polls.blogflux.com/poll-4386.html”>Take the poll</a></p> <p><a href=”http://polls.blogflux.com/” mce_href=”http://polls.blogflux.com/”>Free Poll by Blog Flux</a>
For urologists that subcribe to Contemporary Urology, there was a nice CME article where some of the above facts can be found that gave a nice review of genetic risk factors for prostate cancer.