Diagnosis of Prostate Cancer:What Are the Most Important Things to Know About Diagnosing Prostate Cancer?

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Diagnosis of Prostate Cancer
What Are the Most Important Things to Know About Diagnosing Prostate Cancer?
By Matthew Schmitz, M.D., About.com
Updated: January 9, 2009
About.com Health's Disease and Condition content is reviewed by the Medical Review Board

Every year, thousands of men are diagnosed with prostate cancer. Because of the high numbers of men afflicted with this disease, annual screening tests have been put into place to hopefully catch prostate cancer in its early stages. A number of tests also exist to confirm the presence of prostate cancer after an abnormality is found through screening.

Regular Screening

All men over the age of 50 should be screened annually for prostate cancer. African-American men and men with a strong family history of prostate cancer have been shown to have higher rates of prostate cancer and need to start their screening at age 40 (or even earlier if family members have developed prostate cancer at younger ages).

Additionally, any men who have symptoms suggestive of prostate cancer need to undergo screening.

Appropriate screening involves both a yearly digital rectal exam and prostate specific antigen blood test.

Digital Rectal Exam (DRE)
During this exam, the physician inserts a lubricated, gloved finger (digit) into the rectum. Because of the prostate’s location just in front of the rectum, the physician is able to feel the back edge of the prostate where the majority of cancers begin. Abnormalities such as bumps or hardness of the prostate can be detected in this way.

This test is usually completed in 5 to 10 seconds and most men have very little or no discomfort during it.

Prostate Specific Antigen (PSA) Blood Test
A small sample of blood is taken and then sent to a lab for analysis. PSA is a protein that is only produced by prostate cells. As the prostate enlarges, whether due to cancer or another cause, the amount of PSA produced increases.

High levels of PSA or rapid increases in the PSA level can alert the physician to a possible underlying cancer.

Prostatic Biopsy

If an abnormality is found on the DRE or the PSA test, the physician will typically order a biopsy of the prostate.

A biopsy involves taking a very small sample of tissue from the prostate. This is done using a thin needle that is placed into the prostate. A tiny amount of tissue is trapped in the needle while it is in the prostate and then the needle is pulled out. This is repeated in a number of locations throughout the prostate so as not to miss an area where cancer may be present.

This procedure is usually done by an urologist or other surgeon in their office and involves using local anesthesia to minimize pain.

The tissue samples are then sent to a pathologist (a specialized physician who diagnoses diseases based on their appearance under a microscope) who makes the final diagnosis of prostate cancer.

At this time, the pathologist can also look at the cancer cells to determine how abnormal they are. This is called the cancer’s “grade”. A high grade means that the cells are very abnormal and that the cancer is more likely to spread.

An excellent video is available that illustrates how a prostate biopsy works.

Tests to Determine the Extent of the Cancer

Testing does not stop after the pathologist has determined whether or not cancer is present. In order to treat the cancer effectively, the physicians caring for you must know how far the cancer has spread.

To determine this, a number of tests can be used. Your physician will determine which of these are the best choices for your particular situation, but all work to detect cancer that has spread outside of the prostate.

Ultrasound – A thin ultrasound probe is inserted into the rectum. The ultrasound can show if nearby organs and tissues have been invaded by cancer.

Bone Scan – Prostate cancer often spreads to bones if not detected early. For this reason, this test can be done to provide a detailed picture of the body’s bones. Areas of cancer in the bones can then be detected by your physician.

CT Scan or MRI – These two tests can be used to provide a detailed look at the organs and tissues in the abdomen and pelvis. Only large, bulky areas of cancer outside of the prostate can be seen with these, so they need to be combined with other tests to be most useful.

Lymph Node Biopsy – Lymph nodes are small structures located all over the body. Cancers often spread to nearby lymph nodes earlier than to other tissues. By surgically removing some of the lymph nodes near the prostate and having them analyzed for the presence of cancer, your physician can confirm that the cancer has not spread outside of the prostate.
All of these tests help to determine how far the cancer has spread or the “stage” of your cancer. Staging helps your physician determine the best treatment option for you.

Sources:

Gerber GS, Goldberg R, Chodak GW. Staging of prostate cancer by tumor volume, prostate-specific antigen, and transrectal ultrasound. Urology 40 (4): 311-6, 1992.

Stone NN, Stock RG, Unger P. Indications for seminal vesicle biopsy and laparoscopic pelvic lymph node dissection in men with localized carcinoma of the prostate. J Urol 154 (4): 1392-6, 1995.