The stage of prostate cancer at diagnosis is typically determined by a staging system developed by the American Joint Committee on Cancer (AJCC) called the TNM System along with the Gleason score and the PSA level of the patient.
The TNM system evaluates the tumor based on the following criteria:
- T Category
- The extent of the primary prostate tumor
- N Category
- Whether or not the prostate cancer has spread to nearby lymph nodes
- M Category
- The absence or presence of distant metastasis
Gleason score
The Gleason score is a method of evaluating (from two to 10) how the prostate tumor appears under a microscope. The lower the Gleason score, the closer the tumor looks as compared to normal tissue. The higher the Gleason score, the more the tumor looks abnormal, which increases the likelihood that it will spread.
PSA levels
PSA (prostate-specific antigen) levels measure the amount that this specific protein is found in the blood. The higher the PSA level, the more likely prostate cancer is present.
Stage 4 Prostate Cancer
Prostate cancer that has been diagnosed as Stage 4 is a large tumor that has spread beyond the prostate to organs such as the bladder or rectum (T4), the lymph nodes (N1) or distant organs such as bone (M1). In Stage 4 cancers, the Gleason score and PSA level can fall in any range.
Typical treatment options for Stage 4 prostate cancer may include one or more of the following:
- Radiation Therapy
- This form of treatment uses high energy rays to kill the prostate cancer cells. In Stage 4 prostate cancer, external beam radiation is combined with hormone therapy is some patients.
- Hormone Therapy
- Male hormones – also known as androgens – cause prostate cancers to grow. Hormone therapy options include surgery to remove the testicles, which stops the production of testosterone, a major source for the development of male hormones. Other options include drug therapy including luteinizing hormone-releasing hormone (LH-RH) agonists or antiandrogens, which work to either prevent the testicles from producing testosterone or block the action of testosterone. In Stage 4 prostate cancer, hormone therapy can be given alone as the only treatment or combined with radiation therapy in some patients.
- Surgery
- Surgery performed during Stage 4 is typically reserved to relieve symptoms such as urinary obstruction or bleeding.
- Chemotherapy
- When hormone therapy stops working effectively, several different forms of chemotherapy may be used to treat Stage 4 prostate cancer. These include: carboplatin (Paraplatin), doxorubicin (Adriamycin), estramustine (Emcyt), etoposide (VP-16), mitoxantrone (Novantrone), paclitaxel (Taxol), vinblastine (Velban) and/or vinorelbine (Navelbine).
- Pain Therapy
- When the cancer spreads to other parts of the body, particularly bone, it can cause extreme pain. Pain medications, bisphosphonates, steroids, external radiation or radiopharmaceuticals can be given to help alleviate the bone pain associated with Stage 4 prostate cancer.
- Watchful Waiting or Active Surveillance
- This method, which consists of no active treatment, is usually reserved for men that have another, more serious illness since some treatments for prostate cancer can cause debilitating side effects.
- Clinical Trials
- Depending on the advice of an oncologist, a patient diagnosed with Stage 4 prostate cancer also may consider enrolling in a clinical trial that is studying a new treatment option or a new combination of existing treatment options.
