Prostate cancer signifies the presence of a tumor on the prostate gland. It is an abnormal growth that can be benign (not growing and not lethal, often a pre-cancerous stage) or malignant (growing, spreading and potentially lethal). While urinary problems are common with prostatitis, very rarely is this a symptom of prostate cancer. Prostate cancer often does not cause symptoms until it has spread elsewhere in the body. A bone scan is a definitive way to get a diagnosis of prostate cancer, rather than relying on identifying symptoms.
Where It Spreads
Once the cancer does spread beyond the prostate gland, it is likely to attack the bones. A bone scan is a commonly used test to see if the prostate cancer has metastasized. A bone scan is a test that detect damage to the bones, including damage that cancer can cause to the bones. The scan looks at the entire skeleton and looks similar to an X-ray.
How a Bone Scan Works
The test begins when the doctor injects a radioactive tracer through an IV into the bloodstream through a vein in your arm. This is the only uncomfortable part of the procedure. The tracer is safe for the patient, but it gives off a small amount of radioactivity. The tracer material is gradually absorbed into the bones. After a few hours, a gamma camera, which can detect the radioactivity, is then used to photograph the entire body. The photographing may take up to half an hour. The tracer will be excreted from the patient's body through the urine over the next two or three days.
What the Test Shows
Areas on the skeleton that have had increased growth or breakdown of bone absorb more of the tracer material than normal bone. These active areas show as "hot spots" on the gamma camera pictures. Other areas may not absorb any of the tracer. These show as "cold spots" and are considered abnormal as well. Both hot and cold spots can be indicators of cancer, though they can also indicate other conditions like arthritis or broken bones. A normal bone scan will show that the tracer is evenly dispersed throughout the skeleton.
Drawback
While a bone scan can be an excellent detection tool, it is not an early detection tool. The limitation of the scan is that it most likely won't show anything until up to five years after the cancer metastasizes.
Survival
The key to surviving prostate cancer, as with any cancer, is early detection. The National Cancer Institute looks at survival rates in three categories: local, regional and distant. Nearly 90 percent of prostate cancers are found in the local stage, meaning that the cancer hasn't spread beyond the prostate. The five-year survival rate for local-stage prostate cancer is 100 percent in the United States. If the cancer has spread to nearby areas, it is called a regional-stage prostate cancer and the survival rate is still 100 percent after five years. Distant-stage cancers are those that have spread to areas like the lymph nodes, bone or other organs and the five-year survival rate is only 31 percent.
Tags: bone scan, prostate cancer, survival rate, beyond prostate, cold spots, detection tool, early detection
