What is testicular cancer?

Testicular cancer is a disease in which cells become cancerous in one or both testicles. The testicles (also called testes or gonads) are a pair of male sex glands. They produce and store sperm and are the main source of testosterone (male hormones) in men. These hormones control the development of the reproductive organs and other male physical characteristics. The testicles are located under the penis in a sac-like pouch called the scrotum.

Based on the characteristics of the cells in the tumor, testicular cancers are classified as seminomas or nonseminomas. Other types of cancer that arise in the testicles are rare and are not described here. Seminomas may be one of three types: classic, anaplastic, or spermatocytic. Types of nonseminomas include choriocarcinoma, embryonal carcinoma, teratoma, and yolk sac tumors. Testicular tumors may contain both seminoma and nonseminoma cells.

Testicular cancer accounts for only 1 percent of all cancers in men in the United States. About 8,000 men are diagnosed with testicular cancer, and about 390 men die of this disease each year. Testicular cancer occurs most often in men between the ages of 20 and 39, and is the most common form of cancer in men between the ages of 15 and 34. It is most common in white men, especially those of Scandinavian descent. The testicular cancer rate has more than doubled among white men in the past 40 years, but has only recently begun to increase among black men. The reason for the racial differences in incidence is not known.

What are the risk factors for testicular cancer?

The exact causes of testicular cancer are not known. However, studies have shown that several factors increase a man’s chance of developing this disease.

  • Undescended testicle (cryptorchidism): Normally, the testicles descend from inside the abdomen into the scrotum before birth. The risk of testicular cancer is increased in males with a testicle that does not move down into the scrotum. This risk does not change even after surgery to move the testicle into the scrotum. The increased risk applies to both testicles.
  • Congenital abnormalities: Men born with abnormalities of the testicles, penis, or kidneys, as well as those with inguinal hernia (hernia in the groin area, where the thigh meets the abdomen), may be at increased risk.
  • History of testicular cancer: Men who have had testicular cancer are at increased risk of developing cancer in the other testicle.
  • Family history of testicular cancer: The risk for testicular cancer is greater in men whose brother or father has had the disease.

How is testicular cancer detected? What are symptoms of testicular cancer?

Most testicular cancers are found by men themselves. Also, doctors generally examine the testicles during routine physical exams. Between regular checkups, if a man notices anything unusual about his testicles, he should talk with his doctor. Men should see a doctor if they notice any of the following symptoms:

  • a painless lump or swelling in a testicle
  • pain or discomfort in a testicle or in the scrotum
  • any enlargement of a testicle or change in the way it feels
  • a feeling of heaviness in the scrotum
  • a dull ache in the lower abdomen, back, or groin
  • a sudden collection of fluid in the scrotum

These symptoms can be caused by cancer or by other conditions. It is important to see a doctor to determine the cause of any of these symptoms.

How is testicular cancer diagnosed?

To help find the cause of symptoms, the doctor evaluates a man’s general health. The doctor also performs a physical exam and may order laboratory and diagnostic tests. These tests include:

  • Blood tests that measure the levels of tumor markers. Tumor markers are substances often found in higher-than-normal amounts when cancer is present.
  • Ultrasound, a test in which high-frequency sound waves are bounced off internal organs and tissues. Their echoes produce a picture called a sonogram. Ultrasound of the scrotum can show the presence and size of a mass in the testicle.
  • Biopsy (microscopic examination of testicular tissue by a pathologist) to determine whether cancer is present. In nearly all cases of suspected cancer, the entire affected testicle is removed through an incision in the groin. The surgeon does not cut through the scrotum to remove tissue. If the problem is cancer, this procedure could cause the disease to spread.

If testicular cancer is found, more tests are needed to find out if the cancer has spread from the testicle to other parts of the body. Determining the stage (extent) of the disease helps the doctor to plan appropriate treatment.

Adapted from the National Cancer Institute’s Testicular Cancer: Question and Answer Factsheet: http://www.cancer.gov/cancertopics/factsheet/Sites-Types/testicular