What are the reasons cause false PSA high levels and false low PSA results, which means you have no cancer in your prostate at all and your PSA level was relatively incorrect, come to know and tell your doctor you’re a cancer Free.
A matter of concern for whom deal with prostate cancer testing with PSA blood test as an early cancer marker, you must be aware of things can alter your PSA interpretation, however the professional lab tech must ask you about them before taking a blood sample for prostate specific antigen test.
If you don’t understand the PSA just read> what is the PSA blood test meaning?
What do cause False positive PSA results?
PSA false results mean that’s unlikely you have a prostate cancer and may come from:
- Lab errors: wrong sample, improper handling, storage, inadequate sample as wells as the invalid QC values. To avoid that just take your test in a qualified laboratory.
- Advanced age: cause high normal PSA levels, increasing levels over the time may be interpreted as cancer.
- Prostate biopsy or resection: Prostate biopsy “can lead to a dramatic increase of PSA in serum and keep the PSA value high in one week.” After biopsy, it takes a month or more for PSA to return to baseline. Do PSA test before surgery or must wait for six weeks after surgery to avoid false PSA elevations.
- Indwelling Catheter cause high elevation in PSA results, so that PSA is not useful blood test for prostate cancer when a man has a catheter.
- Injury to pelvic region or prostate
- Prostatitis cause mild elevation but with no clinical significance until it gets worth.
- Riding a bicycle: Physical activities such as riding bicycle, exercise biking, spinning, etc., can cause temporary increase PSA level.
- Sexual intercourse within 24 hours: After ejaculation must wait 24- 48 hours to do the PSA test, ejaculation can produce temporary elevation.
- Testing PSA after prostatic massage for DRE cause false increase in PSA level.
- Drugs of prostatic enlargement: Drugs known as 5-alpha reductase blockers (finasteride or dutasteride), which can be used to treat an enlarged prostate, will lower PSA levels.
- Supplements that effect testosterone: cause high PSA and inverse effect on testosterone results which impacts on seminogram and shows low sperm counts.
- Urinary tract infection cause mild PSA elevation.
- Ultrasensitive PSA blood test (USPSA test) has high sensitivity to detect trace PSA for prediction of the persistence or return of cancer, but can produce false positive PSA results as well.
Don’t miss interpretation of high PSA at: What does elevated PSA mean?
Understanding False Low PSA Results
In general, a low PSA is a good result. However, there are several reasons a PSA test level may be artificially low including:
- Taking statins to lower cholesterol, anti-inflammatory drugs and obesity: that’s because body fat decreases the amount of PSA circulating in the blood stream.
- Over doses of some chemotherapeutic drugs, for instance; cyclophosphamide and methotrexate, can cause false PSA increase or false PSA levels decrease.
What to do when your results show false PSA results?
- Don’t forget to mention what drugs and supplements do you have to your doctor.
- Repeat strange PSA results on another trustful lab.
- When follow up multiple PSA testing, it’s preferred to do blood work with one laboratory, because minimum increase in PSA values can be a clinically significant.
- PSA is a screening test useful as early tumor marker but confirmation is done through DRE and Biopsy.
Other blood tests for cancer detection can help make decision:
- Free PSA/total PSA ratio: the high values are correlated with prostate cancers.
- The percentage of [-2] proPSA test: is relative to the total PSA level as free PSA is used.
- PCA3 test in urine: increasing are produced by 95% of prostate cancer cells,
- Urine test for TMPRSS2-ERG gene fusion: over expressed in 50% of prostate cancers.
- Biopsy from prostate is the best indicator to confirm prostate cancer is present or not, as the most tests used to decide if the biopsy is needed or not.
In this topic you understand the appropriate interpretation for your blood test results.
PSA Chart by age:
PSA Levels are explained well in other topics but here are fast notes on PSA Chart by age and in general.
General PSA level guidelines
• 0 to 2.5 ng/mL is considered safe
• 2.6 to 4 ng/mL is safe in most men but talk with your doctor about other risk factors
• 4.0 to 10.0 ng/mL is suspicious and suggest the possibility of prostate cancer
• 10.0 ng/mL and above is dangerous and should be discussed with your doctor immediately
Age-specific PSA ranges
These reference ranges refer to using different PSA levels to help the physician make a recommendation for a biopsy. The age ranges are as follows:
• 40-49: 2.5
• 50-59: 3.5
• 60-69: 4.5
• 70 and up: 6.5
Understand what’s is the level should PSA be at: What is the normal PSA levels?
Some people say caffeine affects PSA and others ask if physical activities which rubbing prostate elevates PSA. Recent studies showed that there is no connection has been found to caffeine and tests of strenuous bike riding (13 hours on a mountain bike) showed no PSA rise at all. Although a person has to mention to his doctor all his suspicious matters before doing tests, if doctor and lab tech. say it’s OK, then It’s Ok.
Another thing to know is that PSA test has a normal standard deviation and that may show some slight changes in your results from time to time and from lab to lab. So that slight increase over time should be handled carefully and not to get interpretation but from a special lab consultant or from your specialist doctor.
Do my PSA results mean I have a cancer?
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