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A Biopsy Is The Only Certain Way To Diagnose Prostate Cancer

Although there are a number of excellent tests to indicate the possible presence of prostate cancer, such as the digital rectal examination and the prostate specific antigen (PSA) blood test, the only certain way to diagnose the presence of prostate cancer is to carry out a prostate biopsy.

A biopsy will normally be conducted by a urologist and can be done as an 'office' procedure. There are various different ways in which a biopsy can be taken but it is common to start by taking a transrectal ultrasound. Here an instrument is inserted through the rectum and sound waves are used to produce a computer image of the prostate gland. With this image to hand the doctor can then use a hollow needle to take several small samples of tissue from the prostate for examination under the microscope. Most patients would say that the biopsy is not an especially painful procedure, but you will probably feel a stinging sensation.

The areas from which samples are taken, and the number of samples removed for testing, will depend upon the reason for the biopsy. For example, if the biopsy is simply in response to rising PSA levels then half a dozen or more samples may be taken from different areas of the prostate. However, if the biopsy is being done to examine a particular abnormal area of the prostate then only two or three samples may be collected.

Once the samples have been collected they will be examined by a pathologist. Normal prostate cells are typically of a standard size and neatly arranged in a recognizable pattern. However, prostate cancer cells normally vary in size and are irregular in shape.

If the pathologist determines that cancer is present then he will go on to grade the cancer to indicate whether it is a low grade cancer which is likely to be slow growing, or a high grade cancer which may well be aggressive and spread quickly.

In 1977 the pathologist Donald Gleason devised a scale for categorizing prostate cancer and this scale is now widely used today. The Gleason scale ranges from 1 to 5 (with 1 representing a low grade cancer and 5 a high grade cancer) and a grade is assigned to each of two samples from the largest areas of cancer with the grades being added together to produce a final Gleason score.

A Gleason score of 2 to 4 is considered to be low and indicates a cancer which, depending on the age of the patient, may now pose a significant threat during the patient's lifetime. A score of between 5 and 7 is an intermediate grade for which treatment can often halt the disease in its tracks. Once a Gleason score reaches 8 the cancer is said to be aggressive and is likely to spread outside of the prostate gland, if indeed it has not already done so.