Further tests for prostate cancer
How is prostate cancer staged and graded?
Finding out the stage and grade of the cancer is important for the doctor when deciding upon the right type of treatment options for your prostate cancer.
Grading prostate cancer
Grading means seeing how the cancer cells look under the microscope and how different the cancer cells are to normal cells. After a prostate biopsy a doctor called a pathologist will look at the samples (cores) that were taken during the biopsy under a microscope. Depending on how they look, they will be given a grade.
In prostate cancer, the grades are 3,4,or 5. The two most common grade patterns on each core (sample) are then added together to give each core an overall score called the Gleason score.
The overall score of each core (sample) is usually between 6 and 10. Lower Gleason scores are slower growing whereas the higher Gleason scores are faster growing.
Risk based on Gleason score
The grade gives the doctor an understanding of the “growing nature” of the prostate cancer and how quickly the cancer might grow and can help to decide on the best way to treat the cancer. The risk of prostate cancer spreading is often based on the Gleason score as well as how the prostate gland feels when examined by the doctor and the PSA. Your doctor will explain all of this in relation to you and how your biopsy results will influence what treatments are right for you to be thinking about.
Staging of prostate cancer
Staging is a means of finding out whether the cancer has spread beyond the outer shell or capsule of the prostate to the nearby tissue or to other parts of your body. Cancer that is found within the prostate gland only is called localised or early prostate cancer. Cancer that has spread beyond the edge of your prostate to nearby tissues is called locally advanced prostate cancer.
Further tests like x-rays may be used to stage the cancer. Whether you need any staging tests done depends on the grade of your cancer as well as your PSA test results and the feel of your prostate. Your doctor will discuss this with you and will tell you what staging tests you will need, if any. Staging may not be complete until all the different tests are done.
Describing the stages of prostate cancer
There are a few different staging systems for prostate cancer, but the following one is used most often and is called the TNM. This stands for Tumour, Node, Metastasis.
T Describes the size and depth of the tumour:
N Refers to whether there is cancer present in nearby lymph nodes or not
NO Means that there is no cancer in the lymph nodes.
M Means whether there is evidence of cancer spread (metastasis) to other areas of the body or not.
TNM for early stage prostate cancer: T stage 1 or 2 N Stage 0 M stage 0
If the prostate biopsy shows that you have prostate cancer you may need other tests done. These are known as staging tests. These extra tests are very important because they will show if the disease has spread to other parts of your body. The results of the tests will help to decide on the best treatment for you.
The tests may include all or some of the following:
Bone scans are very sensitive and can detect cancer cells before they show up on an X-ray. For this test a very small amount of mildly radioactive substance is injected into a vein, usually in your arm. A scan is then taken of all the bones in your body. Because abnormal bone absorbs more of the radioactive substance than normal bone, it can show up on the scan.
After the injection you must wait for up to 3 hours before the scan can be taken. You may want to take a book or magazine with you or a friend to keep you company. The level of radioactivity used in these scans is very low and safe. It disappears from the body within a few hours.
You may need bone X-rays if the bone scan shows doubtful areas in certain bones. These X-rays will help to confirm whether you have benign (non-cancerous) or malignant (cancerous) bone disease.
CT (computerised tomography) scan
This is a special type of X-ray that builds up a detailed picture of the inside of your body. It does not hurt. Before the scan you may have to fast for 4 hours. You may be given a special drink or injection which helps show up parts of the body on the scan. It is important to let the radiographer know if you are allergic to iodine or have asthma before you take the drink or injection.
The injection may make you feel hot all over for a few minutes. Preparation for a CT scan can vary. The doctor or nurse will tell you what to do. This test is usually done as an outpatient, which means you can go home after the test is done.
This special type of scan uses magnetic energy to build a picture of tissues inside your body. It does not hurt but it can be noisy. You will be given earplugs to wear during the scan. You may have an injection before the scan to show up certain areas of the body. You cannot wear metal jewellery during the scan. Patients who have certain medical devices implanted, e.g. a pacemaker, are not suitable for the test. The doctor in the hospital will advise you. Most people can go home after the scan.
Learn more about tests for prostate cancer.