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NCI Dictionary of Cancer Terms

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The NCI Dictionary of Cancer Terms features 8,214 terms related to cancer and medicine.

We offer a widget that you can add to your website to let users look up cancer-related terms. Get NCI’s Dictionary of Cancer Terms Widget.

free PSA
(free …)
The amount of the protein prostate-specific antigen (PSA) in the blood that is not attached to other proteins. It is compared with the amount of PSA in the blood that is attached to other proteins. The amount of free PSA is higher in men with benign prostatic hyperplasia (BPH).The amount of PSA attached to other proteins is higher in men with prostate cancer.