PSA levels are measured when screening for prostate cancer, monitoring disease progression, and monitoring patient response to prostate cancer treatment.
Specific prostate antigen (PSA) is a glycoprotein found only in the prostate epithelium. Measurement of PSA is considered a reliable indicator of prostate cancer. Older men usually have slightly higher normal PSA values. However, a PSA value greater than 4 ng/mL is considered high and further investigation is needed. It is also important to note that the upward trend in PSA value levels is also assessed. Even if the PSA value is within normal limits, an increase of at least 0.75 ng/mL per year (high rate of PSA change) is considered abnormal and should be investigated. Additional diagnostic tests include a digital rectal exam, an ultrasound scan, and possibly a prostate biopsy.
The total PSA consists of the free PSA and the bound PSA. The rate of free PSA is lower in men with prostate cancer than in men without cancer, because catabolic tumor activity and rapid prostate cancer metabolic rate increase serum PSA without a proportional increase in the level of free PSA. Examination of free PSA involves measuring both free and total PSA and then calculating their proportion. This test is recommended for men with a negative digital rectal exam, accompanied by an elevated level of total PSA. It may help by providing guidance on the selection of patients who need a prostate biopsy, especially when total PSA levels are between 4 and 10 ng/mL.
Prostate-specific antigen measurement is a reliable indicator for prostate cancer detection. The majority of increases in PSA are attributed to benign prostatic hypertrophy, which increases PSA but not more than 10 ng/mL and also produces higher ratios of free to total PSA. Although 70% of men with elevated PSA values do not have prostate cancer, when values are above 50 ng/mL, PSA is 98.5% accurate in predicting that a prostate biopsy will be positive for cancer.
Prostate-specific antigen measurement helps differentiate, classify and identify tumors, preoperative monitoring, postoperative therapeutic interventions, or cytotoxic drug therapy, and in assessing tumor response to various treatment protocols. It may serve as an indicator of the success of total prostatectomy in prostate cancer.
PSA is a more stable molecule than prostate acid phosphatase, an older biomarker of prostate health monitoring, with no daily fluctuations.
Possible Interpretations of Pathological Values
- Increase: Benign prostate hypertrophy (levels up to 10 ng/mL), cirrhosis, impotence, osteoporosis, prostate cancer, prostate infarction, prostate needle biopsy, prostatitis, pulmonary embolism, renal osteopathy, transurethral resection, medical manipulations inside the urethra, urinary retention. Herbal or natural remedies containing: Dendranthema morifolium, Ganoderma lucidum, Isatis indigotica, Panax pseudo-ginseng, Rabdosia rubescens.
- Decrease: Medications: Finasteride (reduces levels by 50%). Herbal or natural remedies containing Glycyrrhiza uralensis, Scutellaria baicalensis, Serenoa repens.
Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. The correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".
Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings, and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.
At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.