What are Prostate Cancer Stages and Grades

What is my prostate cancer stage?

Staging is the process used to find out more about the location of the cancer and if it has spread within the prostate or to other parts of the body.

Knowing the stage of your prostate cancer is very important. It can help you accurately talk about your prostate cancer and discuss treatment options with your medical team. The process of staging involves a biopsy of the prostate cells, as well as imaging scans like ultrasound, MRI scans, and CT scans.

You may hear or see different terms for prostate cancer stages.

• Early-stage prostate cancer is still located within the prostate. It is also called localized prostate cancer, and may also be referred to as stage I (1) or II (2).
• Regional prostate cancer has spread beyond the prostate to nearby areas such as seminal vesicles or lymph nodes. It may also be called locally advanced prostate cancer. Some regional or locally advanced prostate cancers are considered stage III (3).
• Metastatic prostate cancer has spread (metastasized) beyond the prostate and pelvis to other parts of the body. It is also called advanced prostate cancer, or stage IV (4) cancer.

What is my prostate cancer grade?

The grade of your cancer is determined by looking at the tumor cells from the biopsy under a microscope. The prostate cancer grade is described using the Gleason score. This score is used to estimate how aggressive the cancer may be—if and how quickly the tumor may grow and spread.

The pathologist assigns a number to the cells based on how abnormal they appear. The scale goes from 1 (non-aggressive) to 5 (very aggressive). The numbers of the two most common patterns are added together to create a Gleason Score. The Gleason grading system is one of the most important prognostic factors (that will help determine outcomes) in prostate cancer.

For example, in a biopsy where the most common cell type is a 3, and the second most common cell type is a 4, the Gleason score is a 7. However, a biopsy where the most common cell type is a 4 and the second most common cell type is a 3 would also be considered a Gleason score 7. It is important to know that a 3+4 can progress very differently than a 4+3.

Even if a Gleason grade of 5 is not one of the two most common cell types, many pathology reports will still make note of the presence of any grade 5 cells. A Gleason grade 5, even in a small amount, puts you at a higher risk of having the prostate cancer return (recurrence).

The Grade Group is a more recent grading system and is intended to be simpler than the Gleason score. It has five grades - 1 through 5. You might see one of, or both the Gleason score and Grade Group, listed on a hospital pathology report.

Why are the prostate cancer stage and grade important for treatment?

It is important to know where the cancer is located and the risk for spread or recurrence, to determine the best course of treatment. Some treatments are only effective for early-stage prostate cancer. Other treatments may be best for advanced or metastatic prostate cancer.

Grading is especially useful in early-stage disease. If the tumor shows signs of being aggressive, it may make sense to go forward with more aggressive prostate cancer treatment options. If the tumor does not seem aggressive, it may make sense to choose active surveillance and avoid common side effects.

In any case, be sure to discuss the stage and grade with your doctor and healthcare team.

What are the prostate cancer risk categories?

The stage and grade of your prostate cancer, along with other test results, help determine your risk group.

The D’Amico system is one of the most widely used tools for risk assessment. It provides an estimate of the risk of recurrence at five years after treatment. It combines the PSA, Gleason score, and the clinical stage to create low, intermediate, and high risk categories. The higher the risk category, the higher the chance of recurrence is five years after treatment.

The risk categories are below. If one factor is putting you in a lower category but another is putting you in a higher category, then the higher category takes precedent.

Low Risk:

• PSA is less than 10 ng/mL, and
• Gleason score is equal to or less than 6 (Grade Group 1), and
• Tumor is confined to the prostate (clinical stage T1to T2a)

Note: Some very slow-growing tumors are classified as "very low risk." In addition to the above factors, the cancer is not detectable by DRE and fewer than three of the biopsy tissue sample contain cancer cells.

Intermediate Risk:

• PSA is between 10 and 20 ng/mL, or
• Gleason score is 7 (Grade Group 2 or 3), or
• Tumor is still confined to the prostate (clinical stage T2b or T2c)

Note: Those in the intermediate risk group are often divided further into "favorable" and "unfavorable" categories. Favorable generally means less than half of the biopsy cores show cancer. Unfavorable means more than half of the biopsy cores show cancer.

High Risk:

• Gleason score is 8-10 (Grade Group 4 or 5), or
• PSA is greater than 20 ng/mL, or
• Tumor has spread outside the prostate (clinical stage T3)

Note: Some tumors are considered "very high risk." In addition to the above factors, more than four biopsy cores have a higher grade (Grade Group 4 or 5) or the tumor has extended into the seminal vesicles or beyond.

Ask your healthcare team which risk group you are in so you can understand your treatment options.