Once a pathologist diagnoses prostate cancer in a biopsy, he or she will determine the stage of the disease based on a number of criteria.
The international standard for staging cancer is the TNM system, which takes into account the status of the primary tumor, nearby lymph nodes, and distant metastases. There are four stages of cancer:
- Stage T1: The cancer is only in the prostate and cannot be felt during a digital rectal exam.
- Stage T2: The tumor can be detected during a digital rectal exam, but remains confined to the prostate.
- Stage T3: The cancer may have spread outside of the prostate or to the seminal vesicles.
- Stage T4: The cancer has invaded other tissues or organs next to the prostate, such as the bladder or rectum.