Testicular cancer begins when normal cells in a testicle 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). Testicular cancer is almost always curable if found early, and it is usually curable even when at an advanced stage. Another name for testicular cancer is testis cancer.
About the testicles
The testicles are part of a man’s reproductive system. Each man has two testicles, and they are located under the penis in a sac-like pouch called the scrotum. They can also be called testes or gonads. The testicles produce sperm and testosterone, a hormone which plays a role in the development of a man’s reproductive organs and characteristics specific to men.
Types of testicular cancer
Most types of testicular cancer develop in the sperm-producing cells known as germ cells, and are referred to as germ cell tumors. Germ cell tumors in men most commonly start in the testicles but can also develop in other parts of the body, such as the retroperitoneum (the back of the abdomen near the spine), the mediastinum (the central portion of the chest between the lungs), the lower spine, and very rarely, the pineal gland (a small gland in the brain).
There are two different categories of germ cell tumors that occur in the testicles: seminomas and non-seminomas. Generally, non-seminomas tend to grow and metastasize (spread) more quickly than seminomas, but prompt diagnosis and treatment are important for both types of tumors.
Teratoma is a unique type of non-seminoma germ cell tumor. Unlike the other types of germ cell tumors, chemotherapy is not very effective for a teratoma (see Treatment). The primary treatment for teratoma is to remove it with surgery. Although a teratoma is less likely to spread, it needs to be removed because it can turn into a much more dangerous cancer if it is not removed.
This article provides information only on germ cell tumors (seminomas and non-seminomas) of the testicles in men who have reached puberty. Other, less common types of testicular tumors include Leydig cell tumor, Sertoli cell tumor, and carcinomas of the rete testis (a part of the testicles). These can often be successfully treated by surgically removing the affected tissue; however, if they spread to other areas of the body, they are more difficult to treat. Testicular cancer is uncommon in boys who have not yet reached puberty; childhood testicular cancer is approached differently than cancer in teenagers who have been through puberty and adult men. Other types of cancer, such as lymphoma and leukemia, occasionally spread to the testicles. To find out more about cancer that started in another part of the body and spread to the testicles, read about that specific type of cancer.
Find out more about basic cancer terms used in this section.
Looking for More of an Overview?
If you would like additional introductory information, explore the following item on Cancer.Net:
- ASCO Answers Fact Sheet: Read a one-page fact sheet (available in PDF) that offers an easy-to-print introduction for this type of cancer.
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