After urethral cancer has been diagnosed, tests are done to find out if cancer cells have spread within the urethra or to other parts of the body.
The process used to find out if cancer has spread within the urethra or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment.
The following procedures may be used in the staging process:
- Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
- CT scan (CAT scan) of the pelvis and abdomen: A procedure that makes a series of detailed pictures of the pelvis and abdomen, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
- MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of the urethra, nearby lymph nodes, and other soft tissue and bones in the pelvis. A substance called gadolinium is injected into the patient through a vein. The gadolinium collects around the cancer cells so they show up brighter in the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI).
- Urethrography: A series of x-rays of the urethra. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body. A dye is injected through the urethra into the bladder. The dye coats the bladder and urethra and x-rays are taken to see if the urethra is blocked and if cancer has spread to nearby tissue.
There are three ways that cancer spreads in the body.
Cancer can spread through tissue, the lymph system, and the blood:
- Tissue. The cancer spreads from where it began by growing into nearby areas.
- Lymph system. The cancer spreads from where it began by getting into the lymph system. The cancer travels through the lymph vessels to other parts of the body.
- Blood. The cancer spreads from where it began by getting into the blood. The cancer travels through the blood vessels to other parts of the body.
Cancer may spread from where it began to other parts of the body.
When cancer spreads to another part of the body, it is called metastasis. Cancer cells break away from where they began (the primary tumor) and travel through the lymph system or blood.
The metastatic tumor is the same type of cancer as the primary tumor. For example, if urethral cancer spreads to the lung, the cancer cells in the lung are actually urethral cancer cells. The disease is metastatic urethral cancer, not lung cancer.
- Lymph system. The cancer gets into the lymph system, travels through the lymph vessels, and forms a tumor (metastatic tumor) in another part of the body.
- Blood. The cancer gets into the blood, travels through the blood vessels, and forms a tumor (metastatic tumor) in another part of the body.
Urethral cancer is staged and treated based on the part of the urethra that is affected.
Urethral cancer is staged and treated based on the part of the urethra that is affected and how deeply the tumor has spread into tissue around the urethra. Urethral cancer can be described as distal or proximal.
Anatomy of the distal and proximal urethra. Urine flows out of the bladder and leaves the body through the urethra. The part of the urethra that is closest to the bladder is called the proximal urethra. The part that is closest to where the urine leaves the body is called the distal urethra. The urethra is about 8 inches long in men and about 1½ inches long in women.
Distal urethral cancer
In distal urethral cancer, the cancer usually has not spread deeply into the tissue. In women, the part of the urethra that is closest to the outside of the body (about ½ inch) is affected. In men, the part of the urethra that is in the penis is affected.
Proximal urethral cancer
Proximal urethral cancer affects the part of the urethra that is not the distal urethra. In women and men, proximal urethral cancer usually has spread deeply into tissue.
Bladder and/or prostate cancer may occur at the same time as urethral cancer.
In men, cancer that forms in the proximal urethra (the part of the urethra that passes through the prostate to the bladder) may occur at the same time as cancer of the bladder and/or prostate. Sometimes this occurs at diagnosis and sometimes it occurs later.