Staging is a way of describing or classifying a cancer based on the extent of cancer in the body. The most common staging system for prostate cancer is the TNM system. The International Union Against Cancer (UICC) uses the TNM system to describe the extent of many solid tumour cancers.
TNM stands for tumour, nodes, metastasis. TNM staging describes:
There is a system for clinical staging, which describes the extent of tumour prior to treatment based on clinical tests. Pathological staging describes the true extent of cancer in the prostate after it has been removed surgically.
The following staging information is for adenocarcinoma, which makes up 95% of prostate cancers. Transitional cell carcinoma of the prostate is staged as a urethral tumour. Other rare prostate cancers are staged according to their specific type and behaviour.
Primary tumour cannot be assessed.
No evidence of primary tumour.
Tumour cannot be felt and is not visible on imaging.
T1a – The prostate cancer is found accidentally during transurethral resection of presumed BPH, but it makes up 5% or less of the tissue removed.
T1b – The prostate cancer is found accidentally during transurethral resection of presumed BPH, but it makes up more than 5% of the tissue removed.
T1c – Tumour found due to an elevated PSA level.
Tumour is confined to the prostate.
T2a – Tumour involves half a lobe or less.
T2b – Tumour involves more than half a lobe, but not both lobes.
T2c – Tumour involves both lobes.
Tumour has spread beyond the prostatic capsule.
T3a – Tumour extends though the capsule or involves the neck of the bladder.
T3b – Tumour invades the seminal vesicle(s).
Tumour has become attached (fixed) to, or involves, other nearby structures (other than the seminal vesicles): rectum, pelvic wall, bladder.
Regional lymph nodes cannot be assessed
No regional lymph node metastasis
Regional lymph node metastasis
No distant metastasis
M1a – Metastasis to non-regional lymph node(s)
M1b – Metastasis to bone
M1c – Metastasis to other site(s) – lung, liver, kidney
The UICC further groups the TNM data into the stages listed in the table below.
Tumour involves half a lobe or less.
Tumour involves more than half a lobe but is limited to the prostate.
Tumour has spread beyond the prostatic capsule or into the bladder neck or seminal vesicles.
Tumour has become fixed to adjoining structures like the rectum or pelvic wall.
Tumour has spread to regional lymph nodes.
Tumour has spread to distant sites such as lungs or liver.
Recurrent prostate cancer means that the cancer has come back after it has been treated. It may recur in the same location as the original cancer or it may recur in another part of the body (metastatic prostate cancer).
Castrate-resistant prostate cancer, also known as hormone refractory prostate cancer, is cancer that has come back or has progressed while being treated with hormonal therapy. Prostate cancer cells can gradually develop resistance to hormonal therapy.