The role of the indicator today
Prostatic acid phosphatase was the first tumor marker in medical history and has been used for decades to detect prostate cancer. With the advent of PSA, its importance as a screening test has decreased: PSA is more sensitive and detects the disease at an earlier stage. However, PAP has not completely lost its value - it increases mainly in the case of a widespread process with extension beyond the capsule and bone metastases, therefore it is used as an additional indicator in staging and assessing prognosis. Important: the enzyme level increases after prostate massage, rectal examination, catheterization and biopsy, so blood is donated before these manipulations or a few days after them.
Why preparation is so important
The laboratory result is a number, but the correct number can only be obtained if the rules are followed. Eating changes the levels of glucose, lipids and a number of enzymes significantly; physical activity the day before increases CK and AST; smoking affects hormones; time of day is critical for cortisol and testosterone.
Therefore, a “bad analysis” often turns out to be a consequence of impaired preparation, and not an illness, and leads to unnecessary examinations and prescriptions.
General rules for donating blood
- on an empty stomach 8–12 hours, you can drink water
- Eliminate alcohol and intense exercise per day
- no smoking in an hour
- donate blood before physiotherapy, x-rays and massage
- Take medications in advance by agreeing with your doctor
- for hormones in women, take into account the day of the cycle
How to read the result
Reference values depend on the method and equipment of the laboratory, so it is correct to compare results only within the same laboratory. A deviation of a few percent from the normal limit in itself rarely matters - the overall picture and dynamics are important. It is up to the physician to interpret the analysis: an isolated indicator without a clinical context is often misleading.