Prostatic specific antigen for prostate cancer detection

Abstract

Prostate-specific antigen (PSA) has been used for prostate cancer detection since 1994. PSA testing has revolutionized our ability to diagnose, treat, and follow-up patients. In the last two decades, PSA screening has led to a substantial increase in the incidence of prostate cancer (PC). This increased detection caused the incidence of advanced-stage disease to decrease at a dramatic rate, and most newly diagnosed PC today are localized tumors with a high probability of cure. PSA screening is associated with a 75% reduction in the proportion of men who now present with metastatic disease and a 32.5% reduction in the age-adjusted prostate cancer mortality rate through 2003. Although PSA is not a perfect marker, PSA testing has limited specificity for prostate cancer detection, and its appropriate clinical application remains a topic of debate. Due to its widespread use and increased over-detection, the result has been the occurrence of over-treatment of indolent cancers. Accordingly, several variations as regards PSA measurement have emerged as useful adjuncts for prostate cancer screening. These procedures take into consideration additional factors, such as the proportion of different PSA isoforms (free PSA, complexed PSA, pro-PSA and B PSA), the prostate volume (PSA density), and the rate of change in PSA levels over time (PSA velocity or PSA doubling time). The history and evidence underlying each of these parameters are reviewed in the following article.

Do all patients with newly diagnosed prostate cancer need staging radionuclide bone scan? a retrospective study

“…The test lacks both the sensitivity and specificity to accurately detect the presence of PC. PSA is a prostate-specific marker, Clinical Urolo�� Clinical Urolo�� doi: 10.1590/S1677-55382010000600006 not a PC marker (2). Since the dosing of serum PSA is accompanied by failure, variants of PSA measurements have been described in order to increase its accuracy: free/total PSA ratio, age-specific PSA, PSA density and PSA velocity (3).…”

Clinical utility of prostate-specific antigen mass ratio for prediction of prostate cancer detection on a repeated prostate biopsy

“…PSA is influenced by the prostate size or androgens (8,9). Age, ethnicity, and obesity also influence PSA levels (10)(11)(12). None of the currently used PSA cut-offs consistently identify PCa and exclude non-PCa (11).…”

“…One of the biggest drawbacks of the PSA test is that various factors can influence the PSA level (8)(9)(10)(11)(12). Therefore, the authors examined the effects of various factors on PSA levels in a screening population, and finally devised the PSA-MR. PSA-MR is simply defined as the (i) PSA-D multiplied by the plasma volume or (ii) total PSA amount in circulation per prostate volume.…”

Daily Variation of Free PSA/Total PSA Ratio

“…19 Burada tPSA'nın değişimine ilişkin literatürde tartışmalar mevcuttur. [3][4][5]15,20,2 1 Ancak bu oranın payına (serbest PSA) ilişkin değişiklikler konusunda sınırlı literatüre rastlanmıştır. 22,23 PSA'daki değişimlerin analitik ve biyolojik olabileceği belirtilmektedir.…”

“…Antikimotripsine bağlı PSA, sPSA, PSAdansitesi ve PSA hızı gibi PSA'nın özgüllüğünü artıracak yöntemler ortaya çıkmıştır. 3 PSA üzerinde yapılan çalışmalar PSA'nın gün, haftalar ve aylar içinde değişikliklere uğrayacağına dair kanaatlerin ortaya çıkmasına neden olmuştur. [4][5][6][7][8][9] PSA ölçümlerinin tekrar edilmesiyle ortaya çıkan farklı sonuçların analitik ve biyolojik değişimlerden kaynaklandığı ifade edilmektedir.…”