Staging of Prostate Cancer

Being diagnosed with prostate cancer is never an easy thing to hear and you may have a million questions running through your mind. One of them likely is ‘Has the cancer spread and if so, how far?’. Your cancer care team will determine this in a process called staging.

The information will then help your doctors to know how best to treat the cancer using the various treatment options available such as hormone therapy or radiotherapy brachytherapy (seeds) with or without external beam radiation.

How Is The Stage of Prostate Cancer Determined?

There are 2 types of staging for prostate cancer:

• Clinical staging. This is based on the results of a Digital Rectal Exam (DRE), PSA testing, and Gleason score (more information below). Depending on the results you may be referred to for x-rays, bone scans, CT scans, or MRI imaging. These scans can add more information to help the doctor determine the clinical stage.
• Pathologic staging. This is determined with the information found during surgery, as well as the lab results of the prostate tissue removed during surgery, also called the pathology. The surgery that you may have often includes the removal of the entire prostate and some lymph nodes. Examination of the removed lymph nodes can provide more information for pathologic staging.

What Is The TNM staging system?

The TNM system is a tool that doctors use for prostate cancer staging. This system is developed by the American Joint Committee on Cancer. Doctors analyze the results from diagnostic tests and scan rate the following parameters:

• Tumor (T): Rated between T0 and T4, determines the size and location of the primary tumor.
• Node (N): N0 means it has not spread to nearby lymph nodes, N1 means it has.
• Metastasis (M): Describes whether the cancer has spread to other parts of the body.

The combining results determine the stage of cancer for each person. There are 5 stages: stage 0 (zero) and stages I through IV (1 through 4). Once determined by your doctor, a treatment plan can be made.

Gleason score for grading prostate cancer

The Gleason score is another way of grading prostate cancer. The score is given to highlight how much the cancer looks like healthy tissue when viewed under a microscope. Less aggressive tumors generally have an appearance similar to healthy tissue. Tumors that are more aggressive look less like healthy tissue and usually grow and spread to other parts of the body.

• Gleason X: The Gleason score cannot be determined.
• Gleason 6 or lower(Low-grade): The cells look similar to healthy cells, which is called well differentiated.
• Gleason 7 (Medium-grade): The cells look somewhat similar to healthy cells, which is called moderately differentiated.
• Gleason 8, 9, or 10 (High-grade): The cells look very different from healthy cells, which is called poorly differentiated or undifferentiated.

What Are The Prostate Cancer Stages?

The stage of the cancer is determined by combining the T, N, and M classifications. Staging also includes the PSA level and Grade Group.

Stage I: The cancer is in the early stage and growing slowly. The tumor cannot be felt and involves one-half of one side of the prostate or less. PSA levels are low. The cancer cells look similar to healthy cells.

Stage II: The cancer has not spread and is only found in the prostate. PSA levels are medium to low.

• Stage IIA: The tumor cannot be felt through DRE and involves half of one side of the prostate or even less than that. Medium PSA levels and the cancer cells are well differentiated. This stage could also indicate larger tumors found only in the prostate, as long as the cancer cells are still well differentiated.
• Stage IIB: The tumor may be large enough to be felt during DRE. The PSA level is medium. The cancer cells are moderately differentiated.
• Stage IIC: The tumor may be large enough to be felt during DRE. The PSA level is medium. The cancer cells may be moderately or poorly differentiated.

Stage III: PSA levels are high, the tumor is growing, or the cancer is high grade. These factors indicate that locally advanced cancer is likely to grow and spread.

• Stage IIIA: The cancer has spread beyond the outer layer of the prostate into nearby tissues. It may have also spread to the seminal vesicles. The PSA level is high. 
• Stage IIIB: The tumor has grown outside of the prostate gland. It may have invaded nearby structures, such as the rectum or bladder.
• Stage IIIC: The cancer cells across the tumor look very different from healthy cells (undifferentiated).

Stage IV: The cancer has spread outside the prostate.

• Stage IVA: The cancer has spread to nearby lymph nodes.
• Stage IVB: The cancer has spread to distant lymph nodes, other parts of the body, or to the bones.

For more information

If you’re due for a prostate cancer screening or have concerns about your prostate health, call Urology of Greater Atlanta or make an appointment online today.