Stephan L. Werner, M.D., F.A.C.S.
TNM, T1, T1a, T1b, T1c, T2, T2a, T2b, T2c, T3, T3a, T3b, T3c, T4, T4a, T4b, TNM Staging, N0, N+, M0, M+
Staging refers to the extent of the disease. There are several systems that doctors use so that they can easily communicate the extent of the cancer. The current international standard is the T-N-M or Tumor, Nodes, Metastases system. Another system described below, used in prostate cancer is the Jewett-Whitmore, (JW), system of Stage A, B, C or D. Some prostate cancer specialists also use the High risk, Medium risk, Low risk system to help describe prostate cancer that appears confined to the prostate.
T,N,M System describes the cancer in terms of the local extent of the Tumor, the presence or absence of cancer in the lymph Nodes, and whether there are distant Metastases.
Stage T1
T1a
is a tumor found incidentally in men who have had a prostate operation,
usually a TURP, for benign prostate disease. To be T1a the tumor must
comprise less than 5% of the resected tissue and must be well differentiated,
or Gleason grade < 6. T1a is similar to stage A1 in the JW system
T1b is similarly found after a TURP but comprises more than 5% of the tissue, or is of a higher Gleason grade. T1b is similar to JW A2.
T1c is a prostate cancer
found only as the result of an abnormal PSA blood test, with no other signs of
the disease. Many cancers are found in the T1c. Stage T1c is similar to JW
stage B0.
Stage T2
Stage
T2 is a prostate cancer that is confined
to the prostate with no evidence of spread.
T2a is a prostate cancer that
on rectal exam, (DRE), the cancerous nodule feels that it is confined too less
than ½ of 1 lobe of the prostate. Stage T2a is similar to JW stage B1.
T2b is a palpable cancerous nodule that comprises more than half of one lobe of the prostate but is confined to one lobe or side. Stage T2b is similar to JW stage B2.
T2c can be felt on both sides of the prostate.
Stage T3
To be a T3 lesion the cancer must extend beyond the prostatic capsule, either into the surrounding pelvic tissues and/or the seminal vesicles, (glands behind the prostate that produce the seminal fluid).
T3a is a cancer that has extended
beyond the capsule only on one side of the prostate. Stage T3a is similar to JW
stage C1.
T3b cancer has extended on both sides of the prostate. Stage T3a is similar to JW stage C2.
T3c implies that the cancer has
grown into the seminal vesicles on one or both sides. Stage T3c is similar to JW
stage C2. However it also includes cancers that have extended both into the
seminal vesicles and extended beyond the capsule, similar to JW stage C3
Stage T4
Stage T4 refers to prostate cancer that has escaped from the prostate but is still confined to the pelvis. There are no equivalent JW stages.
T4a: the cancer has extended into the bladder neck, or the distal urinary sphincter or the rectum.
T4b: the cancer has invaded the pelvic muscles or is fixed to the pelvic wall.
Stage N
N staging refers to the presence or absence of cancer spread to the lymph nodes or rectum.
N+ refers to the presence of cancer in the lymph nodes or local spread of the cancer to the rectum. Stage N+ is similar to JW stage D1
Sometimes subclassifications are used:
Nx: the lymph nodes cannot or have not been assessed.
N0: describes the absence of cancer spread to the pelvic lymph nodes or rectum.
N1: there is a small amount, < 2cm., of cancer metastases to a single lymph node.
N2: there are either multiple positive lymph nodes < 5 cm. or a single positive lymph node 2-5 cm in diameter.
N3: there are lymph nodes > 5 cm in diameter.
Stage M
Stage M refers to the presence or absence of cancer outside the pelvis. These distant sites of cancer spread are called metastases. Stage M+ is similar to JW stage D2.
Mx: the presence or absence have or cannot be assessed.
M0: there is no evidence of distant metastases.
M1a: there is spread to distant lymph nodes.
M1b: there is spread to bone.
M1c: there is distant spread to soft tissues, i.e. liver, lung, brain.
The Stage of a cancer refers to how far it has progressed. There are several different staging systems but the most commonly used is A, B, C, D. Within each stage there are sub- stages:
Stage A
describes a cancer that is only found by elevated PSA and biopsy, or at
surgery
for obstruction. It is not palpable on DRE. It is localized to the prostate.
This type of cancer is usually curable, especially if it is a relatively low
Gleason grade.
Stage B
Cancer refers to a cancer that can be felt on rectal examination and is
limited
to the prostate. Other tests, such as bone scans or CT/MRI scans, may
be needed to determine this stage, especially if the PSA is significantly
elevated or the Gleason grade is 7 or greater. Many Stage B prostate cancers
are curable.
Stage C
Cancer has already spread beyond the capsule of the prostate into local
organs or tissues, but has not yet metastasized or jumped to other sites. This
stage is determined by Digital Rectal Exam, or CT/ MRI scans, and/or
Sonography. The bone scan, and , if done, the Prostascint scan are negative.
Some Stage C cancers are curable.
Stage D
Cancer has already spread, usually to distant lymph nodes, bones or other
sites. This is usually determined by bone scan, Prostascint scan or other
studies. Stage D cancer is not curable but is treatable
There has been discussion recently about a slightly different classification for planning of therapy of apparently confined prostate cancers: Low, intermediate or high risk.
Low risk comprises those prostate cancer that are low in volume, Stage A or B1/B2, with a Gleason Grade of 6 or less, and a PSA less than 11.
Intermediate risk requires Stage B3 or Gleason Grade 7 or PSA greater than 10.
High Risk includes those cancers B3 or greater, Gleason grade 7 or above and PSA greater than 10.
Stephan Werner, M.D., F.A.C.S.
Rev:02/01
[Top] [Grade] [Treatment Options] [Urologic Conditions]