September 13th, 2010
12:02 AM ET

Study: Men with low initial PSA levels less likely to develop prostate cancer

Men with low PSA levels from a baseline blood test were less likely to develop prostate cancer compared to men whose baseline PSA levels were high, according to a new study.

The simple test may be a strong predictor of who will benefit from future screening and treatment for prostate cancer, according to the study published Monday in the journal Cancer.

More than 85,000 men, ages 55 to 74, with no previous prostate cancer history were the subjects of the study. The authors found that in order to save one life, they needed to investigate almost  25,000 men with low PSA levels but only 133 men with high ones. Similarly, they needed to treat 724 men who had low PSA levels to save one life but only 60 men whose levels were higher.

PSA, or prostate-specific antigen, is a protein found in prostate cancer tissue. When that tissue breaks down, the protein seeps into the bloodstream. The heavier the presence of PSA in the blood, the more likely prostate cancer will be dangerous and require some type of treatment, said Dr. Otis Brawley, Chief Medical Officer at American Cancer Society and a contributor to CNNHealth.com.

But aren't all cancers bad, even if a man's PSA level is low?

"There are a large number of prostate cancers that don't need to be treated because they're not a health threat to the man who has them," explained Brawley.  That makes guidelines for screenings more difficult to set.

The American Cancer Society encourages men to work with their doctors to learn about the test's benefits and risks before making an informed personal decision around age 50.   Research has not yet proven that the potential benefits of testing outweigh the harms of testing and treatment, explains the organization.

The American Urology Association recommends baseline screening for men at age 40 with future screenings determined in conjunction with the patient's doctor.

"This can't be done in a vacuum," said Dr. J. Brantley Thrasher, spokesman for the American Urology Association and the William L. Balk Chair of the Department of Urology at the University of Kansas. "We need to let [patients] know this is an imperfect marker, but we're getting data that may help us in the future."

It's difficult to accept the idea that you could have prostate cancer that doesn't need to be treated and could be left alone with no harm, while other men have aggressive and deadly prostate cancers.  Brawley, who chooses not to be screened, thinks this is why most men get PSA tests regularly, despite the many risks associated treatment.

"By choosing to get screened, there is a guaranteed increase in diagnosis... but there is only a potential decrease in death," said Brawley.

Some of the risks of treatment include impotence, incontinence and bowel injury.

Still, Thrasher says the importance of the PSA blood test should not be diminished. He tells his patients to get regular screenings every other year or every three years after their initial test.

"I believe knowledge is power to some extent," said Thrasher. "It's risks versus benefits... and each decision point is a fork in the road where [me and patients] have to have a discussion."

soundoff (25 Responses)
  1. sally

    My husband had an initial psa of 1.4. A year later it was 3.1. When we insisted on a biopsy(because of extensive family history),all 13 biopsies were positve for cancer. It isn't just the psa number but the amount of increase.We were told,and statistics bear out that action isn't taken until psa is 4 or over. I'm glad we were insistent as after a radical prostatectomy he's 5 years cancer free.

    September 13, 2010 at 09:24 | Report abuse | Reply
  2. austinypc

    About ten years ago, my psa reading rose from 3 to 4 and then to 5 one year later. I had biopsy twice but both shown negative. After that my urologist stopped giving me biopsy even my psi reading has risen to 11 because he believed the psa reading means nothing to me. I hope that better diagnotic method could be developed so that there is no need to 'waste' money to do the biopsy

    September 13, 2010 at 10:18 | Report abuse | Reply
  3. Rich

    Due to BPH I had a prostatectomy in 2005. The removed tissue was 140 grams, against a normal weight of 20-30. In the previous 10 years my PSA was in the 20-22 range. After the surgery my PSA measured in the reange of 1-1.5. The surgeon reported not one grain of cancer in any of the tissue. His view, and I have to accept, is that the test for PSA as a marker for cancer is quite nearly worthless. Also, needle biopsies are of questionable value unless multiple tissue samples are taken at the same time, because the needle may not find the cancer residng in another area of the gland.

    September 13, 2010 at 10:25 | Report abuse | Reply
  4. David Brown

    Prostate Cancer is a very painful way to die. Even with lots of meds the pain can be extremely bad.
    Get yearly check ups.

    September 13, 2010 at 12:10 | Report abuse | Reply
  5. Robert Leung

    Important to note that screening guidelines should include digital rectal exam and PSA testing, not PSA alone.


    September 13, 2010 at 12:28 | Report abuse | Reply
  6. Bruce D

    Your article talks about "low" PSA but doesn't define what low means. Mine was 5.4 and a biopsy with 10 samples showed cancer in 8 of them. I had a radical prostatectomy 5 years ago and have had 6 PSA tests since – all rated as "undetectable" so I guess it was caught in time. However, I've been impotent ever since with minor incontinence for the past 5 years and I still wonder whether the prostatectomy was the right thing to do. Doctors (experts) leave the decision on treatments to the patient and we really don't know which way to go with all these conflicting reports.

    September 13, 2010 at 13:14 | Report abuse | Reply
    • Russ


      I understand the frustration you are feeling. I'm 61 and had a radical prostetectomy last year. My PSA when from baseline 1.7 to 5.3. My biopsy had 7 positive cores and I was scored a 7 on the Gleeson scale. By the time I was operated on (about six months after initial diagonosis) my PSA was up to 8.3.

      While my surgeons were experienced in the nerve sparing surgical technique, I went under the knife having been told that if the nerves were involved they would be taken because their first concern was to get all the cancer. At my age, the risk of permanent impotence was 50/50. Due to the skill of my surgeons, I made a full recovery (including sexual function). Postoperatively, the margins of the removed gland were all negative and I have an unmeasureable PSA level.

      However, you need to remember that having the radiation first effectively precludes having successful surgery later (e.g. the radiation doesn't kill it all) because the damage from the radiation makes discerning the tissue types very difficult.
      If, God forbid, my prostrate cancer returns, by choosing the surgery first, I still have the other treatment options to deal with it.

      And so do you because of the choice you made.

      September 13, 2010 at 16:00 | Report abuse |
  7. Nino Tomizza

    I had surgery 3 years ago, after the operation my psa was 00.3-00.5 then went up to 00.8-0.1.2 , I was told to have 7 week of radiation. After 3 months the psa reading was 0.1.1 still the same. In 6 months I will have another psa test...What that means, I'm I supposed to worry? They are still learning about Prostate Cancer....there is no clear solution.

    September 13, 2010 at 13:17 | Report abuse | Reply
  8. VaSafOf

    I am a Stage IV cancer recovery person, five plus years. Since being discovered and treated for Cancer my PSA has always been above10.00 and has been as high as 14.00, I have had numerous biopsies all negative plus extensive trips to a Urologist. My opinion is PSA levels are bunk. Not worth the time and effort.

    September 13, 2010 at 13:43 | Report abuse | Reply
  9. david

    Be sure you really need a biopsy... check and double-check. After a year of up and down PSA's numbers, my doctor sent me for a biopsy.... two days later I'm in intensive care near death as a result of Ecoli from the test... I was 50 yrs old and my whole world changed as a result of a test that may not have really been necessary. While I was in the ER, there were two other cases just like me – thats what my doctor stated. Anyway, PSA range was based on a sampling or study group but many people can fall outisde of a numerical range that applies to some. As it turns out I didnt have cancer or any indication of such so, like I said make sure you check and double check, get a second opinion because what we think will help us can also kill us as in my case.

    September 13, 2010 at 15:47 | Report abuse | Reply
  10. Bill

    The PSA test saved my life...I had rising levels and when it hit 4.1 I had a biopsy done and found out at age 46 I had prostate cancer.Nothing was detected in the digital exam. The bad part is mine was agressive and if my doctor went by the govt. guidelines it would not have been found until it spread. I chose IMRT instead of surgery because of side effects and the success rates are now the same. Prostate cancer is not the same for each man.Get second or third opinions.

    September 13, 2010 at 16:01 | Report abuse | Reply
  11. Benn

    I just had a biopsy this past June after my absolute PSA reading went from 1.6 in January (this year) to 6.4 in June. While it was cause for concern to my urologist, I decided to research the issue for myself. The results of that research left me somewhat miffed.

    Apparently, there are two (2) schools of thought on PSA readings as a predictor of cancer. One, the traditional school, looks at the absolute number and does not prescribe any treatment until a certain threshold is attained. That "threshold" is somewhat ambiguous but 2.5-4.0 was mentioned by my GP (early on when he fumbled around clearly conflicted about answering a direct question) as a range to pay attention to. He did NOT, however, depend solely on that. Different studies that I looked at suggested that some practitioners in the past didn't 'blink an eye' until 10.0 had been breached.

    The second school of thought deals with the "rate of change" of the PSA reading and clearly my case was cause for concern. This method is known as "PSA Velocity" and recent studies "suggest" that it is a better predictor but no one makes any definitive statement in that regard but instead prefers to address how doctors might treat such cases. Believe it or not, "wait and see" IS a treatment and recent studies in PSA Velocity recommend AGAINST that approach now.

    My doctor established a "baseline" PSA reading several years ago when, having reached 50, I re-established contact with a GP for annual physicals and such. He was very attentive to the movement of that number and generally, it tended to stabilize downward (1.6 was the best reading that I ever attained in this window of study...obviously, 6.4 was the worst.)

    I had 10 sites harvested and all were negative. In the time since, I have found out that a number of things can affect your PSA so the test is not a absolute indicator or a particularly good predictor but it is all medical science has at this time and there is a compelling case based on correlation (bearing in mind that "Correlation does not imply causation").

    The key is to have regular check-ups......

    September 13, 2010 at 16:20 | Report abuse | Reply
    • duffey

      A negative biopsy does not mean you don't have the illness. The Urologist could have missed the cancerous tissues by less then a mm. Stay on top of this, A PSA from 1.6-6.4 is not a good thing. Please have your PSA repeated annually.

      September 13, 2010 at 20:03 | Report abuse |
    • Benn


      Thanks! Yes the rate of change in such a brief time is alarming and we are doing 6 month follow-ups. Frankly, during my research on the issue, I did not run across anyone with a PSA ratio (i.e.- PSAV) comparable to mine which was more than a little frightening....

      There may have been infection at that time but who wants to stand 'pat' on that given the risks. I'm back for more blood work and another reading in October and we'll see what is up then....

      Thanks again.

      September 13, 2010 at 22:55 | Report abuse |
  12. Dr Perry Fisher

    PSA ratio.....psa level/unit s of time

    September 13, 2010 at 16:31 | Report abuse | Reply
  13. duffey

    I had I -131 seed implants after having PSA velocity from 2-3-3.8. The core biopsy of 12 found 2 hot spots. Although ithe treatment was no fun, I'm certainly glad I have that worry off my back. Many treatments , many options. I chose one that I felt would be appropriate to my disease. Regardless of the treatment one chooses, it's important to know the track record of the surgeon who is performing the treatment.

    If they can't give you references, stay away from them.

    September 13, 2010 at 16:31 | Report abuse | Reply
  14. Monika

    I understand there are a lot of things that are not yet known about prostate cancer, but please be diligent about having your check ups anyway. My dad was diagnosed with stage IV prostate cancer in January of 2008. He died a year and a week later in February 2009. He had had urinary problems, went to see a urologist who checked his PSA and was told it was 56. I didn't know what that meant at the time, but I was sure the doctor knew what he was talking about when he said it was just an infection and started him on a course of antibiotics. His PSA went down to 38. After some research, I found a great doctor and got a second opinion. Sadly enough, the cancer had spread to his bones throughout his body and even chemo didn't help. He was an extremely healthy and fit 57 year old man, who died an extremely painful death. I remember on occasion he would say, "why me?", I would like to think it's so that his experience will save someone else. I make my brother go get his checked now. Just please don't take it for granted, it was a horrible year watching him get progressively sicker and knowing the pain medicine wasn't easing his pain. He even had a pain pump inserted in his spine in addition to oral medication. So, please remember to take care of yourselves and get second, third, fourth opinions if you have to! God Bless!

    September 13, 2010 at 17:16 | Report abuse | Reply
    • duffey


      I am so sorry about your Dad. Unfortunatly too many men do not get annual check ups, or neglect to be certain a PSA test is ordered. Your experience and your story takes the debate about NOT getting a PSA.

      Yes your Dad did have a higher purpose for suffering through this illness, and you are fulfilling that purpose on this blog.

      September 13, 2010 at 19:58 | Report abuse |
  15. Benn

    In follow-up to my original comment: maybe it was 12 sites that were harvested but in any case they were all negative....

    As Monika so graciously and generously shares in her personal experience: check-ups are key.

    September 13, 2010 at 18:19 | Report abuse | Reply
  16. Rebecka and renee

    My dad had a lot of urinary pain, was given a psa and got the number 1800. It was 20 months of bad news at doctors offices, taking a needle which cost $1000 per month (or he could have been castrated to stop testosterone production and try to extend his life) there was no chemotherapy that he could take at the time ( the only one available needed a strong heart or it would have killed him) he had some radiation. This was 10 years ago when it seems like there wasn't much options for stage iv diagnosis. He was 59 the first time he got a psa test and almost61 when he died. Just wanted to share my story, don't want to scare anyone. I also read in my studying of the disease that if you have daughters you are at greater risk. It's a slow growing cancer, but my dads wasn't. Doctors were surprised bc he was relatively young. His psa two wkd be foe he died was 4500. Thanks for letting me share my story....

    September 13, 2010 at 23:06 | Report abuse | Reply
    • duffey

      Rebecka and Renee.,
      Your Dad had great daughters who cared about him. This story is testimony of that, and I bet he knew it. A man couldn't be more blessed, and I'm sure he knew that as well.

      September 14, 2010 at 00:13 | Report abuse |
  17. Charles Hartsell

    I have always thought that the treatment for prostate cancer..radium seed implants...chemo...etc. was worse than the disease. I have seen many men lose their quality of life and be sickened with unwarranted treatment. I choose to not have another PSA. last one as 51 was 0.9...We will see was the future holds. at a level of less than 1.0 reading

    September 14, 2010 at 09:48 | Report abuse | Reply
  18. B

    It would be helpful when citing a peer reviewed journal article that you also provide the complete reference to it so that the general public could look up the original article.

    September 14, 2010 at 11:17 | Report abuse | Reply
  19. PPS

    Even before my brother died of prostrate cancer last year at the age of 59, I have been deligent getting my psa checked an average of two to three times annually. I also did the digital rectal exam. My psa reading never exceeded 3.51, however I have been very insisted on geting a biopsy done because of my family history and the small voice inside of me. My doctor did not see the need for it , after two years of bugging him, he finally relented. When I went for the result, I was alarmed to find that I have prostrate cancer. Obviously this affected my confidence in the medical system. I have opted for surgery, even though my doctors feels that we do not have to be aggressive, I find it hard to listen to him any more because he lost me when his first assurance failed. The pain that I saw my brother go through has a tremendous impact on me. I am a single parent with two daughters and cannot afford to take chance. I presently have some minor back problem, even though my doctors assured me that it cannot be from the prostrate cancer. I pray that he is right.

    December 18, 2010 at 19:25 | Report abuse | Reply
  20. pete

    I had a P.S.A.test 4.5 years ago as my number went for 4.0-6.4 in a year. My dr. referred me to a urologist and he did a biopsy. They took 12 specimens and 8 out of 12 were cancerous and 2 were high grade. So actually 10 out of 12 were cancerous. I was shocked to say the least. He aske how many years would i like to live. I was 57 and said 20 or more would be great. He said my best chance would be to have surgery as radiation is no guarantee and if cancer is still there cannot do surgery later. I selected surgery and had it done Robotically with 3 inserts and out my navel glad i had it done as it was 1 millimeter from breaking through. The biopsy is the real thing to go by not the P.S.A. #. A few people I know had P.S.A. numbers were between 8-13+ A few had biopsies and a couple were good and a couple had just large prostates You must have a biopsy to see if you really have cancer.

    May 30, 2012 at 16:46 | Report abuse | Reply

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