Your Screening Examination

Screening for prostate cancer can be performed quickly and easily in a physician’s office using two simple tests: the prostate specific antigen (PSA) blood test, and the digital rectal exam (DRE).

About the PSA Test

PSA is an enzyme produced in the prostate that is found in the seminal fluid and the bloodstream. An elevated PSA level in the bloodstream does not necessarily indicate prostate cancer, since PSA can also be raised by infection or other prostate conditions such as benign prostatic hyperplasia (BPH). Many men with an elevated PSA do not have prostate cancer.

Nonetheless, a PSA level greater than 4.0 ng/mL of serum was established initially as the cutoff where the sensitivity for detecting prostate cancer was the highest and the specificity for detecting non-cancerous conditions was the lowest. A PSA level above 4.0 ng/mL of serum may trigger a prostate biopsy to search for cancer. Recently, experts have argued that men with a PSA level greater than 2.5 should obtain biopsies to increase the likelihood that prostate cancer might be detected earlier in a more curable form of the disease.

It is important to note that the PSA test is an imperfect screening tool. A man can have prostate cancer and still have a PSA level in the “normal” range. Approximately 25% of men who are diagnosed with prostate cancer have a PSA level below 4.0. In addition, only 25% of men with a PSA level of 4-10 are found to have prostate cancer. With a PSA level exceeding 10, this rate jumps to approximately 65%.

More sophisticated forms of the PSA blood test can be used to further improve the precision of the test. It should be noted that the standard PSA test remains the most widely used screening assay for prostate cancer and that the newer methods are just starting to be adopted by the medical community.

About the DRE

The digital rectal exam should be performed along with the PSA test. The DRE is performed by a trained professional who will insert a gloved finger into the rectum to feel the peripheral zone of the prostate where most prostate cancers occur. The examiner will be checking for hardness of the prostate or for irregular shapes or bumps extending from the prostate — all of which may indicate a problem. The DRE is particularly useful because the PSA test may miss up to 25% of cancers, and the DRE may detect some of these.

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