Testicular cancer occurs when cells in the testicles grow out of control and form tumors. The testicles are made up of several types of cells, each of which can develop into different types of testicular cancer.

Overview and Symptoms

The testicles are made up of several types of cells, each of which can develop into different types of testicular cancer. These cells begin to change and grow uncontrollably, forming a mass or tumor. The cells can also invade the blood stream and lymph system and spread, leading to tumors in other areas of the body. The first sign is often a painless lump in one of the testicles. Other signs and symptoms include:

  • A change in how the testicle feels
  • A dull ache in the groin or lower abdomen
  • A build-up of fluid in the scrotum
  • Pain or discomfort in the testicle or scrotum
  • A scrotum that feels heavy or swollen
  • Bigger or more tender breasts

Testicular cancer is highly treatable and one of the most curable forms of cancer. When detected in its earliest stages, the cure rate is usually over 95%. Early detection is the best prevention for the spread of testicular cancer. Most testicular cancers are found by men themselves or their partner. Testicular cancer typically occurs in young men; the average age at diagnosis is 33, although it can affect teenage boys and sometimes men over age 50.

The exact cause of testicular cancer is unknown. A common, but false belief is that it is caused by prior injury or trauma to the testicles, and recurrent actions such as horseback riding or biking. However, there is no scientific evidence that those things are related to the development of testicular cancer.

Types of testicular cancer:

  • Germ cell tumors – about 90% of testicular cancer cases are germ cell tumors, meaning they developed in the germ cells, the cells that make sperm. Germ cell tumors can be seminomas, which usually grow and spread more slowly, or non-seminomas, which tend to grow more quickly.
  • Stromal tumors – sometimes called gonadal stromal tumors, these develop in the supportive and hormone-producing tissues in the testicle, called the stroma.
  • Secondary testicular cancers – these are cancers that start in another organ and spread to the testicle. They are not true testicular cancer – they are named and receive treatment based on the part of the body where they started.

Testicular diagnosis may involve:

  • Physical exam
  • Biopsy – the removal of a tissue sample from the tumor. After removal of the testicular tumor, doctors can then tell what type of testicular cancer you have by looking at the cells under a microscope
  • Blood tests – Some types of testicular cancer can increase blood levels of proteins known as tumor markers. For example, proteins, including human chorionic gonadotropin (HCG) and alpha-fetoprotein (AFP), can be detected by a simple blood test and are considered tumor markers for certain types of testicular cancer.


Depending on the type and stage of your cancer and other factors, testicular cancer treatment can include:

  • Surgery
  • Radiation therapy
  • Chemotherapy (chemo)
  • High-dose chemotherapy and stem cell transplant

More than one of type of treatment might be used.

Testicular Cancer Program

Patients with testicular cancer are treated through the Multidisciplinary Genitourinary Cancer Program, where leading oncologists, surgeons, radiation oncologists, radiologists, and pathologists provide state-of-the-art diagnosis and treatment.

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