QuestionIn 2007 my PSA was 1.1. In 2008 it was 1.6 and in 2009 it was 1.9. All the tests were done at different labs. I'm 63 years old. Is the rise in numbers possibly due to different labs, or are my numbers creeping up in me in a bad way? Thanks for your time.
AnswerHi Jack,
Please be aware that the information provided is not a substitute for medical advice and should not be interpreted as medical advice. This information is being provided for informational purposes only. Your own physician is the best resource to interpret your specific laboratory results and should be consulted for medical advice regarding your own specific health condition.
PSA varies with age however your lab result of 1.9 is still within reference range for your age.
The sensitivity of the PSA is high meaning it will detect all positives that are positive but specificity of the PSA test is low, meaning it will produce a significant number of false positives.
Although reference range results vary from lab to lab since they're based on average ranges of a specific patient populations, the accuracy of the results should not vary significantly.
Below is some additional information on the PSA from LabTestsOnline:
http://www.labtestsonline.org.uk/understanding/analytes/psa/test.html
"The 'normal' value for total PSA varies with age and is generally considered to be under 3.0 nanograms (ng) per millilitre (mL) in men under 60 years of age of blood, under 4.0 ng per mL in men 60 - 69 years of age, and under 5.0 ng per mL in men over 70 years of age. Total PSA levels greater than 10.0 ng/mL may indicate a high probability of prostate cancer. Increased levels of PSA in those with a small prostate gland volume (which can be measured using ultrasound at the time of biopsy) indicate a higher probability of cancer. Levels between 4.0 ng/mL and 10.0 ng/mL may be due to BPH, a non-cancerous swelling of the prostate which occurs most frequently in elderly men."
Elizabeth
