Staging means to determine how invasive the cancer cells are within, around the prostate or around the body – in other words, how far the cancer has spread in the body. There are different ways to stage prostate cancer but they generally indicate the size of the tumor and the level it has spread to other parts of the body.

There are two systems that are commonly used to stage prostate cancer: the TNM staging system and the Whitmore-Jewett staging system.

The TNM staging system: is more specific and tells you about the size of the tumour and where it has spread. T stands for Tumour, N stands for nodes (referring to lymph nodes), and M stands for metastasis (degree of cancer spreading around the body).

T1: Indicates that the cancer cannot be felt or seen by the naked eye
T2: Indicates that cancer is confined to the prostate gland
T3 to T4: Indicates that the cancer has spread past the prostate gland into surrounding tissues.

If the cancer has spread to the lymph nodes, this will be indicated by an N
N1: Indicates a small tumor in the lymph node
N2: Indicates a medium tumor in one node or several small tumors in several lymph nodes
N3: Indicates a large tumor in one or more lymph nodes

If the cancer has spread past the lymph nodes and metastasized this is represented by an M
M1a: Indicates cancer has spread just past the nodes
M1b: Indicates cancer has spread into the bones
M1c: Indicates cancer has spread to other sites in the body.

The Whitmore-Jewett staging system is a more general staging method. In this system the tumor is classified by letters (A to D).

Stage A: Indicates that the cancer cannot be felt or seen by the naked eye
Stage B: Indicates that the cancer is not detectable by the presence of a tumour
Stage C: Indicates that the cancer has spread to surrounding tissues and vesicles
Stage D: Indicates that the cancer has spread to bones and organs throughout the body