Know your PSA test

The PSA test is the standard biomarker for prostrate cancer post treatments. The prostrate gland, pituitary and adrenal glands produce prostrate specific atintgens into our blood stream. There are 6 type of structured PSA antigens. But significantly there are two types of antigenS. Fixed and Free PSAs, fixed as in fixed to a protein and Free as in free for fixing onto a protein. Benign prostrate tumurs produce Free PSA. The standard PSA test shows the total amount of PSA in the blood. But FREE PSA can be counted as a percentage of the total PSA count. The lower the percentage of the Free PSA the higher the chance of cancer cells present. The higher the Free PSA percentage the lower the chance of cancer cells present. Studies have shown the following chances of cancer cells present relative to the amount of Free PSA to Total PSA in the blood.

Under 10% Free PSA means 56% chance of cancer.
10-15% means 28% chance of cancer
15-20% means 20% chance of cancer
20-25% means 16% chance of cancer
25% and above means less than 8% chance of cancer.

The next time you do your PSA test ask for the persentage of Free PSA from your total amount.

Take care.

Allen Lai