While prostate cancer is the second leading cause of cancer-related deaths (after lung cancer), nonetheless in the vast majority of men it is slow-growing and ultimately harmless. Almost 80% of men will get it by the age of 79, and in many of these cases the treatment is worse than the disease itself. However, it is cancer, and like any cancer it can spread to other parts of the body. Stage IV prostate cancer is the type that has spread not only beyond the prostate but to other organs of the body as well, which can then become a serious problem and is considered incurable.

Stage I and II have not spread beyond the prostate, and stage III and IV have. Stage III has spread beyond the prostate, and stave IV has reached other organs.

Of Stage IV, two sub categories are recognized: localized and metastatic. Localized has spread beyond the prostate, but still within the pelvic region. This would include such organs as the rectum, as well as lymph nodes within the pelvis. Metastatic Stage IV has spread outside the pelvic region, involving lymph nodes and organs in other areas of the body. Prostate cancer often spreads to the bones.

The primary means of treatment for stage IV prostate cancer is hormone therapy, done via castration or drugs, which can prolong life for several years by cutting of the supply of male hormones that prostate cancer feeds upon. Eventually, however, the cancer will continue to grow.

In localized stage IV prostate cancer, the hormonal treatment is often combined with external beam radiation therapy for better results. There has also been a lot of research in recent years looking at different combinations of treatments, such as chemotherapy, surgery, and the usual hormone and external beam radiation. In some cases, hormone therapy was delayed until the cancer progressed, but new research indicates that beginning hormonal therapy right away led to improved quality of life and extended survival rates.

Metastatic stage IV, prostate cancer that has spread beyond the pelvic region and involves other organs, most often attacks the bones. Bone cancer can then lead to other problems, such as a dangerous increase in calcium in the bloodstream, fractures, and extreme joint pain. Most often, in addition to hormone therapy, metastatic prostate cancer will also be treated for bone pain.

Drugs called biophosphonates are the most commonly prescribed drug to reduce bone problems. These work by inhibiting cells that break down bones, thus resulting in less pain and fractures. Radiation aimed at the bone cancer is also often used.

Finally, there is a new vaccine available on the market for stage IV prostate cancer sufferers called Provenge. The urologist takes a sample of white blood cells from the patient, sends it to a lab where it is mixed with prostate cancer cells, and then injected into the patient. This primes the white blood cells to attack that particular type of cancer. Studies have shown an increase in lifespan of several months using Provenge, and side effects are few, although it is an expensive treatment (up to $100,000).