context: There are two primary disorders that affect the male reproductive external organs. These include penis disorders and testicular disorders. Disorders of the penis and testes can affect a man's sexual functioning and fertility. The testicles, also called testes, are part of the male reproductive system. The testicles are two oval organs about the size of large olives. They are located inside the scrotum, the loose sac of skin that hangs behind the penis. The testicles make male hormones, including testosterone, and produce sperm, the male reproductive cells. Problems with the testes can lead to serious illnesses, including hormonal imbalances, sexual problems, and infertility. Some of the more common conditions that affect the testicles include testicular trauma, testicular torsion, testicular cancer, epididymitis, and hypogonadism. Because the testicles are located within the scrotum, which hangs outside of the body, they do not have the protection of muscles and bones. This makes it easier for the testicles to be struck, hit, kicked, or crushed, which occurs most often during contact sports. Males can protect their testicles by wearing athletic cups during sports. Trauma to the testicles can cause severe pain, bruising, and/or swelling. In most cases, the testes -- which are made of a spongy material -- can absorb the shock of an injury without serious damage. A rare type of testicular trauma, called testicular rupture, occurs when the testicle receives a direct blow or is squeezed against the hard bones of the pelvis. This injury can cause blood to leak into the scrotum. In severe cases, surgery to repair the rupture -- and thus save the testicle -- may be necessary. Within the scrotum, the testicles are secured at either end by a structure called the spermatic cord. Sometimes, this cord gets twisted around a testicle, cutting off the blood supply to the testicle. Symptoms of testicular torsion include sudden and severe pain, enlargement of the affected testicle, tenderness, and swelling. This condition, which occurs most often in men under the age of 25, can result from an injury to the testicles or from strenuous activity. It also can occur for no apparent reason. Testicular torsion requires immediate medical attention. Treatment usually involves correction of the problem through surgery. Testicular function may be saved if the condition is diagnosed and corrected immediately. If the blood supply to the testicle is cut off for a long period of time, the testicle can become permanently damaged and may need to be removed. Testicular cancer occurs when abnormal cells in the testicles divide and grow uncontrolled. In some cases, certain benign (non-cancerous) tumors may progress and become cancer. Testicular cancer can develop in one or both testicles in men or young boys. Symptoms of testicular cancer include a lump, irregularity or enlargement in either testicle; a pulling sensation or feeling of unusual heaviness in the scrotum; a dull ache in the groin or lower abdomen; and pain or discomfort (which may come and go) in a testicle or the scrotum. The exact causes of testicular cancer are not known, but there are certain risk factors for the disease. A risk factor is anything that increases a person's chance of getting a disease. The risk factors for cancer of the testicles include: Age. Testicular cancer can occur at any age, but most often occurs in men between the ages of 15 and 40. Undescended testicle. This is a condition in which the testicles do not descend from the abdomen, where they are located during fetal development, to the scrotum shortly before birth. This condition is a major risk factor for testicular cancer. Family history. A family history of testicular cancer increases the risk. Race and ethnicity. The risk for testicular cancer in white men is more than five times that of black men and more than double that of Asian- American men. Testicular cancer is a rare form of cancer, and is highly treatable and usually curable. Surgery is the most common treatment for testicular cancer. Surgical treatment involves removing one or both testicles through an incision in the groin. In some cases, the doctor also may remove some of the lymph nodes in the abdomen. Radiation, which uses high-energy rays to attack cancer, and chemotherapy, which uses drugs to kill cancer, are other treatment options. Removing the one testicle should not lead to problems with having sex or children. The remaining testicle will continue making sperm and the male hormone testosterone. To re-establish a normal appearance, a man may be able to have a testicular prosthesis surgically implanted in the scrotum which looks and feels like a normal testicle. The success of testicular cancer treatment depends on the stage of the disease when it is first detected and treated. If the cancer is found and treated before it spreads to the lymph nodes, the cure rate is very high, greater than 98%. Even after testicular cancer has spread to the lymph nodes, treatment is highly effective, with a cure rate greater than 90%. To find testicular cancer early, all men should be familiar with the size and feel of their testicles, so they can detect any changes. Most doctors feel that recognizing a lump early is an important factor in the successful treatment of testicular cancer and recommend monthly testicular self-exams in combination with routine physical exams for all men after puberty. Epididymitis is inflammation of the epididymis. The epididymis is the coiled tube that lies on and around each testicle. It functions in the transport, storage, and maturation of sperm cells that are produced in the testicles. The epididymis connects the testicles with the vas deferens (the tubes that carry sperm). Epididymitis often is caused by infection from a sexually transmitted diseases, including chlamydia and gonorrhea . In men over 40 years of age, the most common cause is due to bacteria in the urinary tract. Symptoms of epididymitis include scrotal pain and swelling. Discharge from the penis, painful urination, and painful intercourse or ejaculation may also be present. In severe cases, the infection can spread to the adjacent testicle, causing fever and abscess (collection of pus). Treatment for epididymitis includes antibiotics (drugs that kill the bacteria causing the infection), bed rest, ice to reduce swelling, the use of a scrotal supporter, and anti-inflammatory medicines ( NSAIDS such as ibuprofen). Partners will need to be treated if the epididymitis is due to a sexually transmitted infection to prevent re-infection. If left untreated, epididymitis can produce scar tissue, which can block the sperm from leaving the testicle. This can cause problems with fertility, especially if both testicles are involved or if the man has recurring infections. The use of condoms during sex can help prevent epididymitis caused by chlamydia or gonorrhea. One function of the testes is to secrete the hormone testosterone. This hormone plays an important role in the development and maintenance of many male physical characteristics. These include muscle mass and strength, fat distribution, bone mass, sperm production, and sex drive. Hypogonadism in men is a condition that occurs when the testicles (also called gonads) do not produce enough testosterone. Primary hypogonadism occurs when there is a problem or abnormality in the testicles themselves. Secondary hypogonadism occurs when there is a problem with the pituitary gland in the brain, which sends chemical messages to the testicles to produce testosterone. Hypogonadism can occur during fetal development, at puberty, or in adult men. When it occurs in adult men, hypogonadism may cause the following problems: Erectile dysfunction (the inability to achieve or maintain an erection) Infertility Decreased sex drive Decrease in beard and growth of body hair Decrease in size or firmness of the testicles Decrease in muscle mass and increase in body fat Lose of bone mass (osteoporosis) Enlarged male breast tissue Mental and emotional symptoms similar to those of menopause in women (hot flashes, mood swings, irritability, depression, fatigue) There are various causes of hypogonadism, including: Klinefelter's syndrome. This syndrome involves the presence of abnormal sex chromosomes. A male normally has one X chromosome and one Y chromosome. The Y chromosome contains the genetic material with the codes that determine the male gender, and related masculine characteristics and development. Males with Klinefelter's syndrome have an extra X chromosome, which causes abnormal development of the testicles. Undescended testicles. (see above) Hemochromatosis. This condition is marked by too much iron in the blood, and can cause the testicles or the pituitary gland to malfunction. Testicular trauma. Damage to the testicles can affect the production of testosterone. Cancer treatment. Chemotherapy or radiation therapy, common treatments for cancer, can interfere with testosterone and sperm production by the testicles. Normal aging. Older men generally have lower levels of testosterone, although the decline of the hormone varies greatly among men. Pituitary disorders. Problems affecting the pituitary gland, (a small organ in the middle of the brain) including a head injury or tumor, can interfere with the gland's ability to send hormonal signals to the testicles to produce testosterone. Medications. Certain drugs can affect testosterone production. These include some commonly used psychiatric drugs. Treatment for hypogonadism depends on the cause. Male hormone replacement (testosterone replacement therapy or TRT) often is used to treat disorders of the testicles. If the problem is related to the pituitary gland, pituitary hormones may help increase testosterone levels and sperm production.