Grading and staging are terms used by doctors to describe tumors (cancer).
- The term "grade" refers to how fast your cancer may spread. For prostate cancer, the Gleason score is used.
- The term "stage" refers to the extent and location of the cancer.
The biopsy result is reported using a measure called a Gleason grade and a Gleason score. Grading is performed by a pathologist who examines the cancerous cells under a microscope and assesses the aggressiveness of these cells.
The Gleason grade describes how fast the cancer might spread. It grades tumors on a scale of 1 through 5. You may have different grades of cancer in one biopsy sample. The two most common grades are added together. This gives you the Gleason score.
The higher your Gleason score, the more likely the cancer can spread beyond the prostate:
- Scores 2 through 5: Low-grade prostate cancer.
- Scores 6 through 7: Intermediate- (or in the middle) grade cancer. Most prostate cancers fall into this group.
- Scores 8 through 10: High-grade cancer
Staging describes if a cancer has spread from where it first began.
- Localized prostate cancer: The cancer is contained within the prostate gland and has not spread to nearby tissues or elsewhere in the body.
- Locally advanced prostate cancer: The cancer has spread outside the prostate gland to the seminal vesicles or surrounding tissue, but not to a distant location.
- Advanced prostate cancer: The cancer has spread to nearby lymph nodes, bones, or elsewhere in the body..
- Your doctor may also use the TNM staging system. This system is used for all cancers to describe the stages more specifically:
- The T part is numbered from T1 to T4. There are also T subtypes. For example, for prostate cancer, T1c is the most common stage. It means a patient has a normal prostate exam (digital rectal exam) but an abnormal PSA blood test.
- N refers to whether the cancer has spread to nearby lymph nodes.
- M refers to whether the cancer has spread (metastasized).
How Is Staging and Grading Done?
The following tests may be done to determine whether the cancer has spread:
- CT scan
- Bone scan
- MRI scan
Sometimes, your doctor can feel a prostate cancer during a rectal exam. However, your doctor will also use other information to help guide treatment and follow-up and give you some idea of what to expect in the future. Other factors the doctor will look at include:
- PSA levels (and related tests)
- Prostate biopsy results. These results may be able to show how many areas of the prostate gland have cancer.
- The Gleason score or grade.
How Is Staging and Grading Used?
It is important to understand that only if and when you have surgery to remove the prostate gland can you and your doctor know for certain the stage and grade of your prostate cancer.
Treatment depends on many things, including your Gleason score, stage of cancer, and your overall health. Your doctor will discuss your treatment options.
American Urological Association Education and Research, Inc. PSA testing for the pretreatment staging and posttreatment management of prostate cancer: 2013 Revision of 2009 Best Practice Statement. Linthicum, MD: American Urological Association Education and Research, Inc. 2013. Available at: www.auanet.org/common/pdf/education/clinical-guidance/Prostate-Specific-Antigen.pdf. Accessed October 3, 2013.
Loeb S, Carter HB. Early detection, diagnosis, and staging of prostate cancer. In: Wein AJ, Kavoussi LR, Novick AC, et al., eds. Campbell-Walsh Urology. 10th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 99.
National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Prostate cancer. Version 4.2013. Available at: www.nccn.org/professionals/physician_gls/pdf/prostate.pdf. Accessed October 4, 2013.
National Cancer Institute: PDQ Prostate Cancer Treatment. Bethesda, MD: National Cancer Institute. Date last modified 8/15/2013. Available at: www.cancer.gov/cancertopics/pdq/treatment/prostate/HealthProfessional. Accessed October 4, 2013.
Wilt TJ, MacDonald R, et al. Systematic review: comparative effectiveness and harms of treatments for clinically localized prostate cancer. Ann Intern Med. 2008;148(6):435-448.
Update Date 10/2/2013
Updated by: Scott Miller, MD, Urologist in private practice in Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.