Treatment depends on the point of diagnosis and the severity of the disease. Small clusters of early stage, prostate cancer can be found in millions of men in an apparently harmless, latent form. It's not unusual for physicians to take a "wait and watch approach" to these early cancers, and monitor the progression of the disease with regular PSA levels and physical examinations. Often the disease can be managed this way for years, as long as progression remains slow. Surgery may be another treatment choice if the tumor is contained and the patient is healthy enough to tolerate the operation.

If the prostate is enlarged and there is a palpable mass, surgery may be indicated to remove as much of the prostate, tumor and surrounding lymph tissue as possible to check for metastasis (spread of the cancer cells). Although surgery can cause nerve damage that impairs sexual function, improved surgical techniques have reduced that risk and surgeons are now better able to preserve sexual function.

Radiation therapy is sometimes used after surgery or instead of surgery, and is targeted directly at the tumor to destroy cancer cells. It also is used in later stages of the disease to relieve pain.

In more advanced forms of the disease, hormonal therapy, with either surgical or other medical intervention, suppresses the activity of male hormones (androgens) that fuel tumor growth. It can be effective for many years, holding the disease at bay, but eventually that effectiveness may subside. Side effects from hormonal therapy can be significant, and include impotence, decreased sexual desire, reduced muscle mass, and tenderness or enlargement of breast tissue.

Chemotherapy has become a more common treatment with the recent development of sophisticated oral medications that are free of the side effects associated with previous chemotherapy regimes such as vomiting, hair loss and fatigue. Chemotherapy can stabilize the disease and inhibit growth. It is used in men who have undergone surgery, but whose disease may recur; who have had surgery and/or radiation, have a detectable PSA level but no cancer spread; or in men with metastatic disease where hormone suppression has ceased to be effective.