2017年4月11日 · What’s Free PSA and How Is It Used to Diagnose Prostate Cancer? A free prostate-specific antigen (PSA) test is used to confirm test results from a PSA test. A PSA test is used to see if...

2022年6月14日 · Three out of 4 men with high overall PSA levels turn out to be cancer-free. A more accurate way to predict prostate cancer is to also look for a second form of PSA called free PSA. The name...

PSA, FREE: This marker measures the amount of PSA in the blood that is not bound to proteins. The free PSA level can help differentiate between prostate cancer and benign conditions. Typically, men with prostate cancer have lower levels of free PSA relative to their total PSA because cancer tends to produce more bound PSA.

2023年4月14日 · A free PSA test measures the level of prostate-specific antigens (PSA) that are not bound to other proteins in the blood. This helps diagnose prostate issues.

PSA exists in serum in multiple forms: complexed to alpha-1-anti-chymotrypsin (PSA-ACT complex), unbound (free PSA), and enveloped by alpha-2-macroglobulin (not detected by immunoassays). Higher total PSA levels and lower percentages of free PSA are associated with higher risks of prostate cancer.

前列腺特异性抗原（PSA）是由前列腺上皮细胞分泌的一种蛋白酶，其正常功能是水解液化精液中的凝块，与男性生育力有关。 正常情况下，PSA直接分泌到前列腺导管系统内。 而由于前列腺导管系统周围存在一道血液和上皮之间的屏障， PSA无法直接进入血液之中，从而维持了血液中PSA的低浓度。 但上皮细胞的癌变会破坏 血—上皮屏障，PSA就能够直接进入血液，而且癌症的恶性程度越高，对于正常前列腺组织破坏越大，再加上癌细胞也会增加PSA的分泌。 于是 …

2025年1月21日 · PSA自由行/全部比例. 目前最常用的就是所謂「自由態」的 free PSA (fPSA) 與總 total PSA (tPSA) 的比值。一些 PSA 在血中是不與蛋白質結合的，這些fPSA，在有癌症的情形下，fPSA/tPSA 比值會降低；因此，如果低於某一特定值，臨床上癌症的可能性就增加了。

針對您的問題，PSA（前列腺特異性抗原）和Free PSA（游離前列腺特異性抗原）是評估男性前列腺健康的重要指標。 PSA主要由前列腺細胞產生，當前列腺受到刺激、發炎或腫瘤影響時，PSA的數值可能會上升。

The percent-free PSA (%fPSA), also known as the free/total PSA ratio (f/t PSA), is the ratio of how much PSA circulates free compared to the total PSA level. The percent-free PSA is lower in men who have prostate cancer than in men who do not.

The free to total PSA test is a comparison between the total and free PSA levels in the blood. The free to total PSA test may be recommended when standard PSA tests show high PSA levels for your age. Free PSA levels may help identify benign prostatic hyperplasia, as free PSA is more commonly associated with non-cancerous prostate conditions.