What is testicular cancer?

Testicular cancer is a disease in which cells become malignant (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 ornonseminomas. Other types of cancerthat 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.

  Fighting Testicular Cancer

  Daniel J.'s Story

  By Angela Generoso
  MedicineNet.com
  Reviewed by William Shiel, MD, FACP, FACR
  His scar is small, about four to five inches on his lower abdomen, just above the groin area. He doesn't really notice it much anymore, but the six-year memory lives vividly in his mind.
  Daniel J. was never aware of the importance of self-exams for signs of testicular cancer, until he became a patient himself. As a 25-year-old delivery man at a local flower shop in Oakland, Calif., with no health insurance, he was more than unprepared when the situation arose. Looking back, he is surprised how little is done to inform the male population of the dangers of testicular cancer throughout adolescence.
  "I came home from work on a Saturday, and within a couple of hours, I started feeling pain in my groin," Daniel said. "My scrotumwas swollen and tender."
  Thinking he had simply strained himself at work that day, Daniel took a nap, hoping it would just go away. But when he woke up later that evening, the pain was still there.
  Daniel recalls doing a quick search online to figure out what his symptoms meant. Among the possibilities, he saw the wordstesticular cancer and started to become nervous.
  "It was just a possibility at that moment, so I didn't have any specific reason to believe that was the cause," Daniel said. "I went to the emergency room, and I was clinging to the hope that it was a herniaor something simple. Anything but cancer."