Stages of Prostate Cancer: What Do Stages 1 - 4 Mean?

After someone learns that they have prostate cancer, the next step is staging. It is the process of determining the tumor’s location, if it has spread, where it has spread, and how it is affecting the patient. Basically, staging determines how much cancer is in the body. Here’s what you need to know about the stages of prostate cancer.

Everything You Need to Know About Prostate Cancer

Prostate Cancer Stages: Staging involves several tests

Before we explain the stages, please remember that doctors cannot accomplish staging using just one test.

In prostate cancer, you will most likely need to undergo screenings such as the digital rectal exam (DRE) and blood test to determine your PSA levels. From these, the doctor will order imaging tests such as x-ray, magnetic resonance imaging (MRI), or bone scan. Only after all necessary test results have been gathered will staging be complete.

In general, prostate cancer stages consider 3 things

To determine your prostate cancer stage, the doctors will consider 3 things: your Gleason score, PSA levels, and the TNM classification.

Gleason score

To determine your Gleason score, the doctor will collect cell samples and observe them under the microscope. The goal is to see how aggressive the cancer is. Basically, less aggressive tumors can resemble healthy cells, while aggressive cancer looks less like healthy cells.

The scores look like this:

• Grade 6 or lower means the cell sample looks like healthy cells
• Grade 7 means the cell sample somewhat looks like healthy cells
• Grade 8, 9, or 10 means the cell sample looks very different from healthy cells

PSA Levels

PSA stands for prostate-specific antigen. People who have prostate cancer often have elevated PSA levels.

TNM Classification

The next thing that doctors consider to determine the stages of prostate cancer is the TNM classification. TNM stands for:

• Tumor – Where is the tumor located, and how big is it?
• Nodes – Has the tumor affected the nodes? If yes, what nodes and how many are affected?
• Metastasis – Has cancer spread to other parts? If yes, where and how much?

Doctors use various tests to arrive at the TNM classification. When all results are in, they will then ascertain the stage.

Stages of prostate cancer

Stage I

Typically, there are no symptoms in prostate cancer stage 1. In fact, the doctor often doesn’t feel the tumor during routine DRE or see it in the ultrasound. At this stage, they are likely to find out through tests or incidentally for another concern.

Similarly, a tumor that can be felt during DRE or seen during an ultrasound can be classified under stage 1; that is if it affects half (or less than half) of one side of the prostate.

The patient’s PSA level is low; the Gleason score is 6 or less.  Moreover, the tumor has not spread beyond the prostate.

Stage II

Stage II prostate cancer is further divided into three subgroups: IIA, IIB, and IIC.

The doctor may or may not feel or see the tumor during exams, but cancer at this stage is generally confined in the prostate. Moreover, the Gleason scores typically increase as you move further into the subgroups.

It’s also worth mentioning that, while the tumor at stage II is small, it might have an increased risk of growing or spreading.

Stage III

Like stage II prostate cancer, stage III has three subgroups: IIIA, IIIB, IIIC.

In stage IIIA, the tumor may not have spread outside the prostate, but at IIIB, it may have already extended to nearby structures such as the bladder or rectum.

At stage IIIC, the Gleason score may be 8 or 9, which means the cells look very different from healthy cells.

Stage III prostate cancer essentially means the patient has high PSA levels. It may also indicate that the cancer is locally-advanced, and it shows signs of growing and spreading.

Stage IV

The final phase of prostate cancer stages is stage IV, which has two subgroups: IVA and IVB.

In stage IVA, cancer has spread to lymph nodes. In stage IVB, cancer has spread to distant lymph nodes and other parts of the body.

Early Prostate Cancer Signs Men Should Know

The importance of early detection

Detecting prostate cancer at its earliest stage usually means better treatment outcomes.

Because of this, men must undergo DRE and PSA testing regularly. The age by which they need to start testing varies. But, if you have a very high risk of prostate cancer, due to family history and other risk factors, it’s important to consider testing at the age of 40.

Learn more about Prostate Cancer here.