Tumours contained within the prostate or nearby are classed from T stage 1 to T stage 4:^26,29,31,32

·      T1 – cancerous prostate cells can only be detected under the microscope and the cancer is too small to show on a scan or be felt by DRE;

·      T2 - early or localised PC is used when the cancer is limited to the prostate gland. Often symptom free, it is detectable by DRE or a scan;

·      T3 - locally-advanced PC where cancer has started growing through the capsule surrounding the prostate gland;

·      T4 – locally advanced PC where the cancer has spread to nearby lymph nodes and other organs such as the bladder, rectum, or pelvic wall.

Advanced or metastatic PC is used for cancer which has spread to other parts of the body, typically lymph nodes, bones (further away in the pelvis, other joints, vertebrae, ribs, skull or elsewhere), or other organs such as the lungs, liver, bladder or bowel.^26,29,33

The tumour score is usually given with a nodes and metastases score, the TNM. For nodes, N0 means no cancer has been found in the lymph nodes, whereas N1 indicates cancer cells have need found in lymph nodes near the prostate.²⁹

Similarly, M0 means no metastases have been detected, while M1a means cancer has spread to lymph nodes outside the pelvis, M1b means cancer has spread to bones, and M1c means cancer has spread to other body parts, such as the lungs.