As a medical technologist for over 30 years and as a core lab supervisor for 26, I can tell you that a man's PSA (prostatic specific antigen) will rise (somewhat) as he ages. Slightly elevated values for men over the age of 70 (ish), may be perfectly normal and not indicative of any disease state. When this test is used as the sole indicator of disease state (and unfortunately it often is due to the publicity it has received), many men undergo unnecessary invasive procedures, entailing additional risk and emotional duress. The PSA assay was developed only as a screening tool, to be used in conjunction with a physical exam and other clinical indications. if malignancy is suspected in an older man, much more specific testing is available for help with the diagnosis. (Of course it is also more expensive and must be indicated for insurance reimbursement). Any lab value should ALWAYS be interpreted as part of the entire clinical picture.
The same scenario has occurred recently concerning the use of mammograms for older women. False positives have led to many many unnecessary invasive procedures and mental anguish.
Also always remember that a biopsy (of anything) is only diagnostic if it is positive; there is always the possibility that of biopsy missed the malignant portion of whatever was being biopsied... Medical science is far from perfect, and "standard of practice" is not always the appropriate course of action. For me personally, I've found a doc I trust, stay as informed as I can, and am not at all afraid to ask questions and to ask to see the medical literature his decisions are based upon..
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