Cancer is an unregulated growth of cells. The testes have two types of cells, one cell type which makes sperm (germ cells) and a second cell type which support these germ cells. Cancer of the testes or testicular cancer is almost always an excessive growth of the germ cells. It is the most common cancer of men between 20 and 40, but only represents 1% of all cancer cases in men. Testicular cancer is more common in white males and is also becoming more common over time, though the reason for this is not known.
There is generally no cause found for testicular cancers. The risk of developing testicular cancer is increased if you have a testicle that did not come down into the scrotum (undescended testes), or one that was late to be put into the scrotum (maldescended). There can also be a slightly increased risk if a brother or father had cancer of the testes.
Testicular cancer is usually found as a hard lump in the testes, which is usually painless.
An ultrasound of the scrotum is used to check the lump in your scrotum (the sack surrounding the testes). Once a cancer has been diagnosed, more tests such as a CT scan, will be performed to check if the cancer has spread. Blood tests are also important as they look for hormones in the blood, which can be present in higher levels than normal in people who have cancer.
Testicular cancer is highly curable in its early stages. Depending on the stage at which it is diagnosed, surgery alone can be used, or you may need to have radiotherapy and/or chemotherapy as well.
Surgery removes the abnormal testicle and also sometimes some of the surrounding tissue. After surgery, the testes are looked at by a pathologist to see what type of testicular cancer is present. Depending on the type of cancer you have and whether the cancer has spread, you may be offered further treatment. Note that you only need about half of one testicle to make enough testosterone (male sex hormone) to feel male and to have erections. You need about three quarters of testes to be fertile.