Staging and Grading
Once the diagnosis of prostate cancer has been made the disease has to be staged and graded. The stage refers to the extent and spread of the disease while the grade refers to the nature (aggressiveness) of the particular tumor. Staging will determine the extent of disease and provide important prognostic information that will influence the management decisions.
- X-rays of lumbar spine and pelvis
- Chest X-ray
- Radionuclitide bone scan
- MTI scan of pelvis
TNM Staging system
T stage (extent of primary lesion)
- T1 - tumour confined to prostate, not palpable or visible on TRUS
- T2 - tumour palpable or visible on TRUS but confined to prostate
- T3 - spread beyond the prostatic capsule
- T3a - extracapsular spread only
- T3b - involvement of the seminal vesicles
- T4 - invasion into rectal wall, bladder neck or pelvic wall
N (Nodal) status
- N0 - regional nodes not involved
- N1 - regional nodes involved by tumour
M (Distant Metastases)
- M0 - no distant metastases
- M1 - distant metastases present
Grading refers to what the cancer looks like under a microscope. The most commonly used system is the Gleason grade and score. The glandular pattern is compared to that of a normal prostate and scored out of 5, where 1 resembles a pattern very close to normal and 5 resembles severely distorted glandular architecture. The two predominant glandular patterns within the cancer are graded out of 5 and the combined score calculated out of 10. The higher the Gleason score, the more aggressive is the tumour and the worse is the prognosis.
Patients with cancers confined to the prostate (T1 and T2) and no involvement of the lymph nodes or other organs (N0 and M0) are potentially curable by surgery or radiotherapy. Patients with disease beyond the prostate are not curable.
Prevention of prostate cancer
What is the prostate and what is its function?