Today, two primary classification systems are used to describe the stages of prostate cancer. Depending on which hospital or physician you are seeing for your prostate cancer care, either or both could be used.
It is important to have a basic understanding of the two systems and what they describe.
The TNM System
The TNM system for describing prostate cancer uses the letters “T”, “N”, and “M” to signify “Tumor,” “Nodes,” and “Metastasis.”
The “T” describes the primary tumor (meaning the tumor that has started growing inside the prostate itself). The staging system goes from T0 to T4 depending on the size of the tumor and whether it has extended outside of the prostate itself. Higher numbers mean greater growth of the tumor. Each of the T levels can be further broken down to give a more detailed description of the primary tumor.
The “N” describes the nodes (lymph nodes) that are near the prostate. N0 means that the nodes do not show evidence of cancer, while N1 means that they do.
The “M” describes whether distant metastasis (spread) of the cancer has occurred. M0 means that no distant metastasis has been found and M1 means that it has been found. M1 can be further broken down to describe where in the body the metastasis has occurred.
As an example, a cancer staged as T2cN0M0 would mean a tumor that is found in both lobes of the prostate, has not spread to the lymph nodes, and has not metastasized to distant sites.
The Jewett System
The Jewett System uses the letters A through D to describe four broad staging categories. These can then each be broken down into more detailed descriptions (such as A1 or A2).
Essentially, the four stages can be summarized as follows:
- Stage A – The tumor is undetectable by examination and is only found incidentally during surgery.
- Stage B – The tumor is found only in the prostate gland itself.
- Stage C – The tumor is found only in the area in and around the prostate, but has extended through the capsule that contains the prostate. It could also be found in the seminal vesicles.
- Stage D – The tumor has metastasized to areas distant from the prostate.