Prostate Cancer Diagnosis
Prostate cancer is curable when detected early. However, because the early stages of
prostate cancer may not have any symptoms, it often goes undetected until the patient goes
for a routine physical examination. Diagnosis of the disease is made using some or all of
the following tests.
Prostate cancer diagnosis - Digital rectal examination (DR)
In order to perform this test, the doctor puts a gloved, lubricated finger (digit) into
the rectum to feel for any lumps in the prostate. The rectum lies just behind the prostate
gland, and a majority of prostate tumors begin
in the posterior region of the prostate. If the doctor does detect an abnormality, he or
she may order more tests in order to confirm these findings.
Prostate cancer diagnosis - Blood tests
Blood tests are used to measure the amounts of certain protein markers, such as
prostate-specific antigen (PSA), found circulating in the blood. The cells lining the
prostate generally make this protein and a small amount can be detected in the
bloodstream. However, prostate cancers produce a lot of this protein, and it can be easily
detected in the blood. Hence, when PSA is found in the blood in higher than normal amounts
(for the patient's age group), cancer may be present.
Prostate cancer diagnosis - Transrectal ultrasound
A small probe is placed in the rectum, and sound waves are released from the probe.
These sound waves bounce off the prostate tissue and an image is created. Since normal
prostate tissue and prostate tumors reflect the sound waves differently, the test can be
used to detect tumors quite efficiently. Though the insertion of the probe into the rectum
may be slightly uncomfortable, the procedure is generally painless and only takes 20
minutes.
Prostate cancer diagnosis - Prostate biopsy
If cancer is suspected from the results of any of the above tests, the doctor will
remove a small piece of prostate tissue with a hollow needle. This sample is then checked
under the microscope for the presence of cancerous cells. Prostate biopsy is the most
definitive diagnostic tool for prostate cancer.
If cancer is detected during the microscopic examination of the prostate tissue, the
pathologist will "grade" the tumor. This means that he will score the tumor on a
scale of 1 to 10 to indicate how aggressive the tumor is. Tumors with a lower score are
less likely to grow and spread than are tumors with higher scores. This method of grading
tumors is called the Gleason system. This is different from "staging" of the
cancer. When a doctor stages a cancer, he gives it a number that indicates whether it has
spread and the extent of spread of the disease. In Stage I, the cancer is localized in the
prostate in one area, while in the last stage, Stage IV, the cancer cells have spread to
other parts of the body.
Prostate cancer diagnosis - X rays and imaging techniques
A chest x ray may be ordered to determine whether the cancer has spread to the lungs.
Imaging techniques (such as computed tomography scans and magnetic resonance imaging),
where a computer is used to generate a detailed picture of the prostate and areas nearby,
may be done to get a clearer view of the internal organs. A bone scan may be used to check
whether the cancer has spread to the bone. |