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Introduction to Testicular Cancer

Although cancer of the testes is rare, accounting for only about 1 percent of all cancers in men of all ages and about 5 percent of all male genitourinary system cancers, it is the most common cancer in men between the ages of 15 and 35, and the second most common malignancy in men ages 35 to 39.

Fortunately, testicular cancer is often curable. The treatment success is due to effective diagnostic methods, including identification of tumor markers; effective combinations of chemotherapy drugs; and improved surgical techniques.

Testicular cancers almost always occur in just one testis rather than both; however, about two to three percent occur in both testes either at the same time or successively. The cancer cells grow rapidly but are very susceptible to chemotherapy and radiation therapy.

Because the incidence of testicular cancer has risen markedly in the past 20 years, numerous studies are being conducted to explore possible environmental causes, including the mother's diet during her pregnancy as well as her use of diethylstilbestrol (DES) to prevent miscarriage. Researchers are also looking at the increasing presence of estrogen-mimicking pollutants in the environment. The most consistent occupational association has been the elevated rate among men in professional and white-collar occupation, which may be linked to an increased risk observed with lower levels of exercise.

Other possible causes include hereditary factors, genetic anomalies, congenital defects involving the reproductive tract, testicular injury, and atrophy of the testes. Viral infections such as mumps, which cause inflammation of the testes, have not been proven to cause cancer.