Staging is a method of describing where the cancer is located, where it has spread, and whether it is affecting other parts of the body.
Prostate cancer staging is based on a number of different factors, including prostate cancer screening tests, such as the digital rectal exam (DRE) and the prostate-specific antigen (PSA) test.
Doctors use diagnostic tests to determine cancer’s stage. Staging may not be complete until these tests are finalized. Knowing the correct stage helps the doctor decide the best course of treatment and the possible outcomes.
The Clinical Stage – The clinical stage is based on the results of tests that can be done prior to the surgery. They include the DRE, biopsy, X-rays, CT and/or MRI scans and bone scans. X-rays, bone scans, CT scans and MRI scans may not always be needed. They are recommended based on the PSA level, the size of the cancer, which is determined by its grade and volume and the clinical stage of the cancer.
The Pathologic Stage – The pathologic stage is based on information found during surgery, plus the laboratory results referred to as pathology, of the prostate tissue removed during surgery. The surgery often includes the removal of the entire prostate and some lymph nodes.One important part of the staging process is determining the grade of the cancer. The grading system is based on the microanalysis of the prostatic tissue. While the stage of the cancer is determined based on the macro appearance of the tumor, in connection with the nearby organs and tissues, the grade of cancer is usually determined after a biopsy, when the cells are analyzed under a microscope.
In the 1960s, Dr. Donald Gleason developed a prostate cancer grading system, called the Gleason Score. Dr. Gleason noticed that normal prostate cells go through 5 distinctive patterns until they transform into tumor cells. Based on this differentiation, prostate cells are scaled from 1 to 5. Grade 1 cells have the same appearance as the normal cells, while grade 5 cells are tumor mutations that cease to resemble the normal cells. Gleason grade can vary from 1 to 5, grade 1 cells are considered low-grade and grade 5 cells are considered high-grade. The Gleason Score is calculated based on the Gleason Grade.
The pathologist who examines the biopsy sample will identify 2 important cells patterns and will determine
The 2 grades that were assigned will then be added together and result in the Gleason Score. The Gleason Score can vary from 2-10, but usually, pathologists assign scores between 6-10, 6 being the lowest cancer score.
For instance, if the Gleason Score is written 4+3=7, this means 4 is the grade assigned to the most cancerous cells, while 3 is the grade of the next largest section of the tumor. Together they make up the total Gleason Score, in this instance 7.
A Gleason Score of 6 is considered low-grade. It describes cancer cells that resemble the normal cells and, therefore, the cancer is slow-growing.
A Gleason Score of 7 is considered an intermediate grade, with a medium risk of aggressive cancer. In this case, it is very important to know what is the primary grade (of the largest area). If the primary grade is 3 and the secondary grade is 4, the cancer is not that likely to spread so quickly or cause important problems while a Gleason Score of 7, with the primary grade of 4 and the secondary grade of 3 is more likely to be more aggressive and high-risk.
Consider asking about your primary Gleason Grade, especially when your Gleason Score is 7 and the Gleason Grades are not specified.
A Gleason score of 8-10 is considered to be high-risk. Cancers are likely to spread more quickly and be more aggressive.
For a better understanding of your particular situation, do not hesitate to contact a urologist!
The ISUP Grade Group is a simpler grading system, released in 2014 by the International Society of Urological Pathologists. The ISUP Grade Group is formed by just 5 grades, ranging from 1-5, based on the Gleason Score Value.
There are hospitals that report both the Gleason Score and the ISUP Grade Group, so it is very important to know the significance of both values.
In order to determine the stage of a patient’s prostate cancer, most doctors start by using the TNM staging system, which helps describe different aspects of cancer’s growth and spread. The TNM staging system stands for tumor, node, and metastasis:
Tumor (T) – What is the size of the original tumor? Has it invaded the nearby tissues?
Node (N) – Has the tumor spread to the lymph nodes? If so, where and how many lymph nodes are involved?
Metastasis (M) – Has cancer metastasized (spread) to other parts of the body? If so, where and how much?
In stage 1, the cancer is confined to the prostate. Stage 1 prostate cancer can’t be detected during a digital rectal exam (DRE) and is usually expected to be slow-growing. The tumor is one half of one lobe of the prostate or even less (T1/T2a). There is no regional lymph node metastasis and no distant metastasis. (N0/M0). The PSA level is below 10ng/ml. The Grade Group is 1.
In stage 2, cancer can be detected during a digital rectal exam (DRE). It’s still confined to the prostate, but the cells may be more abnormal and may grow faster.
In stage 3, cancer has now spread beyond the prostate and may have potentially spread into the nearby seminal vesicles.
In stage 3, cancer has now spread beyond the prostate and may have potentially spread into the nearby seminal vesicles.
Prostate cancer is the second leading cause of cancer death in the United States. A man’s individual survival depends on the stage of cancer. Most prostate cancers (90%) are identified at an early stage when they are organ-confined. According to the American Cancer Society, the 5-year survival rate for men with local or regional prostate cancer is nearly 100%. The relative 10-year survival rate is 98% and the 15-year relative survival rate is 91%.
However, if the cancer is stage IVB and has spread to distant parts of the body such as the lungs, liver, or bones there is only a 30% relative 5-year survival rate.
Things to consider when understanding the statistics:
Early detection makes this deadly disease curable. Do not ignore any prostate cancer signs or symptoms and get screened as early as possible, especially if you are at high risk of developing prostate cancer, based on your family history, race or age. Talk to your doctor about your Gleason Score, Grade Group and Stage and decide upon the best treatment option for prostate cancer.
1. TNM Staging, Cancer Research UK, Web
2. Prostate cancer: diagnosis and staging, PubMed, Web, 1 Dec 2018
3. The prostate cancer staging guide, Prostate Cancer Research Institute, Web
4. Prostate Cancer Stages, Johns Hopkins Medicine, Web