Screening
Screening and Diagnosis
Screening for prostate cancer is critical in the early detection of the disease when no symptoms are present. Early detection can minimize future side effects and increase treatment effectiveness. The screening normally involves simple tests performed by your physician.
Prostate Specific Antigen
The prostate specific antigen (PSA) blood test is one of the methods used to determine the likelihood of prostate cancer. PSA is an enzyme produced by the prostate which is found in semen and in the bloodstream. An elevated level of PSA could be an indication of prostate cancer.*
*Although the PSA test is a common tool used by physicians to diagnose prostate cancer, it is important to note that the results are not definitive and would need further evaluation. Many men with a high level of PSA do not have prostate cancer. These high levels could also indicate other types of prostate diseases such as benign prostatic hyperplasia (BPH), a benign noncancerous enlargement of the prostate. Similarly, a normal level of PSA does not necessarily indicate that prostate cancer does not exist.
Digital Rectal Exam
Another prostate cancer screening test is the digital rectal exam (DRE).*
- DRE usually accompanies the PSA test DRE is performed by your physician who inserts a gloved, finger into the rectum to feel for an enlarged or hardened prostate, lumps or other abnormal textures
- DRE may catch some of the 25% of cancers missed by the PSA test
*Although the PSA and DRE tests are important screening techniques, they can not definitively diagnose prostate cancer. These tests are used to determine whether further evaluation is needed.
Transrectal Ultrasound
If your PSA and DRE screenings indicate a need for further testing, your physician may suggest a transrectal ultrasound (TRUS) as a next step. (see Figure 1)
A TRUS is a procedure that uses sound waves to create an image of the prostate. It is used to detect abnormal prostate growth but is of limited value on its own. TRUS is more effectively utilized as a guide in a biopsy procedure.
Figure 1
Biopsy
A biopsy is the removal of tissue samples, which is later examined under a microscope to check for the presence of cancer. During a biopsy, a TRUS is used to guide the needle or needles to remove six or more samples from different parts of the prostate. Some physicians may take 12 tissue samples to be sure that no cancerous tissue is missed.*
- A biopsy is normally performed under local anesthesia
- A biopsy is an outpatient procedure and usually does not require an overnight hospital stay
*A prostate biopsy is the only way to accurately diagnose prostate cancer. However, although it is the most accurate method in detecting the disease, it is still possible to miss a cancer or receive false results after a biopsy. Prostate cancer does not typically form as one single tumor, but rather made up of many small tumors or cancer cells in different areas of the prostate. It is for this reason, and because the tissues extracted are only a sampling and not a complete composition, prostate cancer is difficult to detect with biopsy needles. If there are other strong indications of prostate cancer, the patient should consider repeating a biopsy if no cancer was found in the results of the original procedure.
