Biking, PSA, and Prostate Cancer

[PeterR]

A PSA test is a controversial but recommended screening test for prostate cancer. Has anyone any knowledge as to the possibility of serious biking (5K + miles annually) affecting a PSA test score? Two different, and highly respected, urologists tell me this is highly unlikely.
Thanks for your input

[JohnS]

Then why are you questioning them? PSA stands for "prostate specific antibodies" I believe, which are manufactured when the body is fighting against cancer cells in the prostate. Riding has nothing to do with it.

[dehoopta]

A review of the medical literature agreed with your Urologists. The following is an abstract from one of the articles:

The effect of bicycle riding on serum prostate specific antigen levels.

Crawford ED 3rd, Mackenzie SH, Safford HR, Capriola M.

Department of Urology, Presbyterian St. Luke's Hospital, Denver, Colorado, USA.

PURPOSE: We determined if bicycle riding causes an increase in prostate specific antigen (PSA) levels. MATERIALS AND METHODS: Baseline PSA levels were measured from all 260 volunteers before a 250-mile bicycle ride. After this 4-day race PSA was again measured and this level was compared to the pre-race levels. RESULTS: The overall change from baseline to post-race PSA in all 260 men was 0.069 ng./ml. The change for the 256 men with normal baseline PSA (0.0 to 4.0 ng./ml.) was 0.044 ng./ml. The 4 men with an already elevated PSA (more than 4.0 ng./ml.) showed a large change of 1.65 ng./ml. CONCLUSIONS: There is no statistically or clinically significant increase in PSA after bicycle riding. However, the few participants with an initially elevated PSA had an increase after bicycle riding, although this change does not represent the population and more research is warranted to define further its clinical implications.
:banana:

[gasman]

Then why are you questioning them? PSA stands for "prostate specific antibodies" I believe, which are manufactured when the body is fighting against cancer cells in the prostate. Riding has nothing to do with it.
Actually, PSA stands for Prostate Specific Antigen. It is produced in the prostate and is elevated for a large variety of reasons like infection,trauma, after a prostate exam, cancer and prostate enlargement.
Your prostate slowly grows as you get older which is why older men have difficulty urinating and why older men often have higher PSA values. This is why the test is controversial-the test can show a somewhat elevated value and it may or may not be due to cancer. Prostate cancer is very common esp as men age but it is frequently small, localized and slow growing. The question then is do you treat the cancer ? Prostate cancer rarely kills, so maybe you just watch the PSA for a while.
Does the PSA rise with bike riding ? Well it can if it causes prostatitis ( a prostate infection) but that can be treated with antibiotics.
Does bike riding cause prostate cancer ? No, there is no evidence that it does no matter how much you ride. They may find evidence sometime but none exists now.
Should you have a PSA checked ? Yes, if you are over 50 or have family history of prostate cancer. I had mine checked as I just turned 50 this year.
So ride away.

[pbbob]

turned 50. didn't get mine checked. just got the finger.

[gasman]

turned 50. didn't get mine checked. just got the finger.
I did too-hated it; but still got the PSA- I'm a chicken.

[PeterR]

Thanks for the input and discussion. My experience started with PSA testing at age 55. Subsequent annual screenings were always in the 2.2 - 2.4 range until three years ago when it jumped to 8.1. A second sample was 5.6, but the resultant six point biopsy proved to be negative. Next years results were 7+ and 5 + in a followup sample. This fall a detached retina problem kept me mostly unsaddled for six weeks. My annual test, taken last week, came back normal at 2.4 with the only change in activity being the absence of biking. Hence my curiosity as to the possiblity that biking could be a factor in an abnormally high PSA number. Note that the rise in PSA coincided with 6K plus mile biking years.

[BumbleBeeDave]

. . . can be indicative of any kind of trauma--NOT just cancer--as gasman says, then I think it’s reasonable to assume that 6k miles of cycling might be interpreted by your body as trauma and cause the elevated level, even if there’s no cancer. That’s a lot of riding when you think about it--especially if you live somewhere that the riding season is shorter than the full calendar year. If you have an eight month riding season, that’s almost 190 miles per week for 32 straight weeks--a LOT of riding.

My suggestion would be to ask your doctor if there are are additional tests that can be combined with the PSA test to provide a more definitive check for cancer as you continue riding into your later years. I remember reading somewhere that by age 90 almost 100% of men have some form of cancer in the prostate. I have also read that while it is a slow growing cancer, detecting it early could mean the difference between radiation or chemo vs. more, er, radical solutions that would be pretty uncomfortable--like taking it out.

BBDave