Predicting and Monitoring Advanced Prostate Cancer

Prostate cancer is a complex disease. Doctors cannot always predict how fast or slow it will grow. Nor do they agree on when to treat it, or which treatments to use. Predicting and monitoring the disease with accuracy help doctors and patients make decisions that result in the best survival rates and quality of life.

Predicting Aggressive Prostate Cancer

If you are diagnosed with prostate cancer, your doctor will probably evaluate several factors to determine how aggressive it is. These "markers" identify whether the cancer is low risk, intermediate risk, or high risk. Low-risk prostate cancer is slow growing and not likely to spread quickly. High-risk prostate cancer is aggressive, meaning it is likely to spread quickly outside the prostate. Understanding the risk level of your cancer will help your doctor decide on the treatment that's right for you. Your doctor will look at key "markers" for aggressive cancer, as well as the "stage" of your specific cancer.

Commonly used markers include:

• Prostate-specific antigen (PSA) levels. PSA is a substance produced by the prostate gland. It is normal to secrete small amounts of PSA into the bloodstream. But larger amounts of PSA in the bloodstream usually signal that the prostate gland is enlarged, infected, or diseased. Doctors can determine PSA level by a simple blood test. The higher the number, the more likely the patient is to have cancer. According to the National Cancer Institute, a PSA level of between 0 and 2.5 is low; 2.6 to 10 signals a slightly to moderately elevated level; 10 to 19.9 is moderately elevated; and 20 or more is significantly elevated.
• PSA velocity. Several studies indicate that when PSA levels increase sharply in the months before surgery, the cancer is likely to be aggressive.
• Gleason score. The Gleason score "grades" tumors on the basis of how abnormal they look when the tissue is examined under a microscope. The more abnormal they look, the more likely they are to grow fast and to spread to other parts of the body. A grade of less than 4 generally means that cancer cells look similar to normal cells. Grades 5 to 7 fall under the intermediate range. Grades 8 to 10 indicate aggressive growth.

The stages of prostate cancer refer to the cancer size and how far it has spread. The stages are:

• Localized Prostate Cancer. At this stage, the tumor is confined to the prostate. It cannot be felt, nor can it be seen via imaging techniques. Doctors refer to this as stage I prostate cancer. Disease that is more advanced, but still remains within the prostate, is considered stage II prostate cancer.
• Regional Prostate Cancer. The tumor has grown through the prostate capsule, either into the seminal vesicles (a pair of glands next to the prostate) or into nearby muscles and organs. Doctors call this stage III prostate cancer.
• Metastatic Prostate Cancer. The tumor has spread to the pelvic lymph nodes or more distant parts of the body. Metastatic cancer frequently spreads to the bones. It is also referred to as stage IV prostate cancer.

Though these markers help doctors determine a patient's best treatment options, other factors count too. "Doctors also look at the general health of a patient, his age, and any (other illnesses) as well," says Charles Drake, PhD, assistant professor of oncology at the Johns Hopkins Kimmel Cancer Center. It's also important that doctors learn patients' wishes and concerns, explains Nancy Dawson, MD, professor of medicine and director of Genito-Urinary Medical Oncology at the University of Maryland Greenebaum Cancer Center. "Learning what's important to patients should be part of the treatment decision process," she says.