After penile cancer has been diagnosed, tests are done to find out if cancer cells have spread within the penis or to other parts of the body.
The process used to find out if cancer has spread within the penis 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 tests and procedures may be used in the staging process:
- CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, 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 areas inside the body. A substance called gadolinium is injected into 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).
- Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram.
- 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.
- Biopsy: The removal of cells or tissues so they can be viewed under a microscope by a pathologist to check for signs of cancer. The tissue sample is removed during one of the following procedures:
- Sentinel lymph node biopsy: The removal of the sentinel lymph node during surgery. The sentinel lymph node is the first lymph node to receive lymphatic drainage from a tumor. It is the first lymph node the cancer is likely to spread to from the tumor. A radioactive substance and/or blue dye is injected near the tumor. The substance or dye flows through the lymph ducts to the lymph nodes. The first lymph node to receive the substance or dye is removed. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are not found, it may not be necessary to remove more lymph nodes.
- Lymph node dissection: A procedure to remove one or more lymph nodes during surgery. A sample of tissue is checked under a microscope for signs of cancer. This procedure is also called a lymphadenectomy.
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 penile cancer spreads to the lung, the cancer cells in the lung are actually penile cancer cells. The disease is metastatic penile 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.
The following stages are used for penile cancer:
Stage 0 (Carcinoma in Situ)
In stage 0, abnormal cells or growths that look like warts are found on the surface of the skin of the penis. These abnormal cells or growths may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.
In stage I, cancer has formed and spread to connective tissue just under the skin of the penis. Cancer has not spread to lymph vessels or blood vessels. The tumor cells look a lot like normal cells under a microscope.
In stage II, cancer has spread:
Stage III is divided into stage IIIa and stage IIIb.
In stage IIIa, cancer has spread to one lymph node in the groin. Cancer has also spread:
In stage IIIb, cancer has spread to more than one lymph node on one side of the groin or to lymph nodes on both sides of the groin. Cancer has also spread:
In stage IV, cancer has spread:
- to tissues near the penis such as the prostate, and may have spread to lymph nodes in the groin or pelvis; or
- to one or more lymph nodes in the pelvis, or cancer has spread from the lymph nodes to the tissues around the lymph nodes; or
- to distant parts of the body.