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About the penis
The penis is the external genital organ of a man. It is made up of three chambers of spongy tissue that contain smooth muscle and many blood vessels and nerves. The corpora cavernosa makes up two of the chambers that are located on both sides of the upper part of the penis. The corpus spongiosum is located below the corpora cavernosa and surrounds the urethra, the tube through which urine and semen leave the body at an opening called the meatus. At the tip of the penis, the corpora cavernosa expands to form the head of the penis, or glans.
About penile cancer
Cancer begins when normal cells change and grow uncontrollably, forming a mass called a tumor. A tumor can be benign (noncancerous) or malignant (cancerous, meaning it can spread to other parts of the body). Penile cancer is a rare form of cancer that occurs mostly in uncircumcised men (men who have a foreskin, the piece of skin covering the head of their penis). Circumcision is the removal of the foreskin and may reduce the risk of penile cancer.
Types of penile cancer
There are several types of penile cancer, including:
Epidermoid/squamous cell carcinoma. Ninety-five percent (95%) of penile cancer is epidermoid, or squamous cell, carcinoma. This means that the cells look like the tissues that make up skin when looked at with a microscope. Squamous cell carcinoma can begin anywhere on the penis; however, most develop on or under the foreskin. When found at an early stage, epidermoid carcinoma can usually be cured.
Basal cell penile cancer. Under the squamous cells in the lower epidermis (one of the layers of the skin tissues that cover the penis) are round cells called basal cells. These can sometimes become cancerous. This is also called non-melanoma skin cancer. Less than 2% of penile cancers are basal cell cancers.
Melanoma. The deepest layer of the epidermis contains scattered cells called melanocytes, which make the melanin that gives skin color. Melanoma starts in melanocytes, and it is the most serious type of the skin cancer. This cancer sometimes occurs on the surface of the penis. Learn more about melanoma.
Sarcoma. About 1% of penile cancers are sarcomas, which are cancers that develop in the tissues that support and connect the body, such as blood vessels, smooth muscle, and fat. Learn more about sarcoma.
This section covers cancer that begins in or on the penis. Learn about cancer that starts in the testicles.
Find out more about basic cancer terms used in this section.
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