If your prostate cancer spreads to other parts of your body, your doctor may tell you that it's "metastatic" or that your cancer has "metastasized."
Most often, prostate cancer spreads to the bones or lymph nodes. It's also common for it to spread to the liver or lungs. It's rarer for it to move to other organs, such as the brain.
It's still prostate cancer, even when it spreads. For example, metastatic prostate cancer in a bone in your hip is not bone cancer. It has the same prostate cancer cells the original tumor had.
Metastatic prostate cancer is an advanced form of cancer. There's no cure, but you can treat it and control it. Most men with advanced prostate cancer live a normal life for many years.
The goals of treatment are to:
- Manage symptoms
- Slow the rate your cancer grows
- Shrink the tumor
Some cancers are called "locally advanced." That means the cancer has spread from the prostate to nearby tissue. It's not the same as metastatic cancer since it hasn't spread to other parts of your body. Many locally advanced prostate cancers can be cured.
How Prostate Cancer Spreads
Cancer cells sometimes break away from the original tumor and go to a blood or lymph vessel. Once there, they move through your body. The cells stop in capillaries -- tiny blood vessels -- at some distant location.
The cells then break through the wall of the blood vessel and attach to whatever tissue they find. They multiply and grow new blood vessels to bring nutrients to the new tumor. Prostate cancer prefers to grow in specific areas, such as lymph nodes or in the ribs, pelvic bones, and spine.
Most break-away cancer cells form new tumors. Many others don't survive in the bloodstream. Some die at the site of the new tissue. Others may lie inactive for years or never become active.
Chances of Developing Metastatic Prostate Cancer
About 50% of men diagnosed with local prostate cancer will get metastatic cancer during their lifetime. Finding cancer early and treating it can lower that rate.
A small percentage of men aren't diagnosed with prostate cancer until it has become metastatic. Doctors can find out if it's metastatic cancer when they take a small sample of the tissue and study the cells.
How Doctors Find Metastatic Prostate Cancer
When you are diagnosed with prostate cancer, your doctor will order tests such as:
- CT scans
- MRI scans
- PET scans
These tests may focus on your skeleton and in your belly and pelvic areas. That way doctors can check for signs that the cancer has spread.
If you have symptoms such as bone pain and broken bones for no reason, your doctor may order a bone scan. It can show if you have metastatic cancer in your bones.
Your doctor will also ask for blood tests, including a check of PSA levels, to look for other signs that the cancer is spreading.
PSA is a protein made by the prostate gland. A rise in PSA is one of the first signs your cancer may be growing. But PSA levels can also be high without there being cancer, such as if you have an enlarged prostate or a prostate infection.
If you've been treated, especially if a surgeon removed your prostate, your PSA levels should be so low they can't be found on a test. The presence of any PSA after surgery is a concern.
Any rise in PSA after radiation or hormone treatment suggests the possibility the cancer is spreading. In that case, your doctor may order the same tests used to diagnose the original cancer, including a CT scan, MRI, or bone scan. The radiotracer Axumin could be used along with a PET scan to help detect and localize any recurrent cancer.
Though very rare, it's possible to have metastatic prostate cancer without a higher-than-normal PSA level.
On average, 8 years pass from the time a man is first diagnosed with prostate cancer to the discovery that it has become metastatic. If you've had prostate cancer, work with your doctor to check your risk and set a schedule for routine PSA checks.