A biopsy is needed to confirm that prostate cancer is present in your body. After the diagnosis is confirmed, it is classified into grades. All of this grading, staging, and PSA level can be confusing. We will try to help you make sense of the information you are being bombarded with.
First, PSA is a substance made in the prostate gland. The PSA level is usually low unless the patient has a higher count. A higher PSA level often signals a problem with the prostate and possibly cancer.
Cancers are graded which is a mark of the differences between the cancer cells and the normal cells. These cells are inspected through a microscope and graded on a “Gleason" grade.
The Gleason grading system uses a range from 1 to 5. If your cancer is graded as 1, it means the cancer cells that are clustered together look like normal prostate tissue.
If the cancer cells do not resemble normal cells at all, the grade could be a 5. Doctors will examine the two areas of the prostate that has cancer cells and grade them individually. Those grades are then added together and will be on a scale from 2 to 10.
A low Gleason score means that your cancer is a slow growing cancer. If it is a high-grade, your number is high on the grading scale; it means the cancer could be more aggressive in its growth.
Sizing the Cancer
Staging is another measurement that your doctor will talk to you about. Staging is rating the size of the cancer and where it is found. It also will tell you if the cancer has spread to nearby lymph nodes, the bones, or other organs in the body.
Staging is necessary so you and your doctor can decide how aggressive your treatment should be and which treatment is best for you.
There are two methods used to stage prostate cancer. There is a traditional method that classifies into four categories, A through D, and the second is TNM. This acronym stands for Tumor-Nodes-Metastases. The staging for the A-D method is:
A is early cancer. It means the cancer is only found within the prostate gland and cannot be felt by a rectal exam.
B is the stage when the tumor is found in the prostate gland and can be felt during a rectal exam.
In Stage C, the cancer is more advanced and has spread outside the prostate to surrounding tissue. Stage C cancer has not spread to lymph nodes or other organs.
Stage D is the most serious stage. It means the cancer has spread to the lymph nodes and other sites in the body. That can include the ribs, spine, or other bones or organs.
TNM staging is a little simpler method. It looks at the tumor stage (T), if the cancer has spread to the lymph nodes (N) and if the cancer has metastasized (M) to other sites of the body. Tumor stages are ranked as 1-4, lymph node involvement is graded N for zero, or 0-3.
Metastasis is rated O or 1. MO means there has not been any metastasis and M1 means it has traveled to another location in the body.