The testicles (or testes) are two egg-shaped glands inside the scrotum (the bag under the penis in men) that make male hormones and sperm. Cancer that forms in the testis (one of the two glands) is called testicular cancer and usually occurs in adolescents or young males. The two types of testicular cancer are seminomas--slow growing, radiation-sensitive cancers--and nonseminomas--different cell types that grow more rapidly. The exact cause of testicular cancer is unknown, but there are several risk factors described by the National Cancer Institute (NCI) and the American Cancer Society (ACS).
Undescended Testicles
The testicles usually descend from the abdomen of the fetus and into the scrotum before birth. An undescended testicle, also called cryptorchidism, does not move into the scrotum. The risk of testicular cancer increases when one or both testicles do not descend. Surgery to correct the undescended testicle does not change the increased risk of testicular cancer. The risk of testicular cancer applies to both testes even when only one is undescended, according to the NCI's "Testicular Cancer: Questions and Answers" publication.
Congenital Anomalies
A congenital anomaly or abnormality is also referred to as a birth defect. According to the NCI, a baby born with an abnormality of the testes, penis or kidneys or with an inguinal hernia (a weakening of the area in the groin between the thigh and abdomen allowing fat or intestines to bulge out), has an increased risk of testicular cancer.
Family History
If a brother or father has testicular cancer, the risk to the individual is increased. It is important to know the family history related to birth defects, undescended testicles or testicular cancer. While no single gene has been identified related to inherited testicular cancer, an NCI study found several gene changes related to testicular cancer in family groups.
History of Testicular Cancer
Men who have testicular cancer in one testicle are at an increased risk of cancer in the other testicle, according to the American Cancer Society.
Age
While testicular cancer can occur at any age, it is most common in young males between the ages of 15 and 34, according to the American Journal of Men's Health.
Race
The American Cancer Society reports that testicular cancer is more common in white men than in black men.
HIV Infection
According to the American Cancer Society, there is some indication that HIV infection may increase the risk of testicular cancer.
Body Size
American Cancer Society studies show that tall men have a greater risk of testicular cancer.
References
- American Journal of Men's Health: Incidence of Testicular Cancer in the United States, 1999-2004
- Cancer Epidemiology: Public Perceptions of the Harms and Benefits of Testicular Cancer Education: A Qualitative Study
- Endocrine Related Cancer: Familial Testicular Germ Cell Tumors in Adults: 2010 Summary of Genetic Risk Factors and Clinical Phenotype
