Testicular cancer occurs in the testicles (testes), which are located inside the scrotum, a loose bag of skin underneath the penis. The testicles produce male sex hormones and sperm for reproduction.

Compared with other types of cancer, testicular cancer is rare. But testicular cancer is the most common cancer in American males between the ages of 15 and 35.

Testicular cancer is highly treatable, even when cancer has spread beyond the testicle. Depending on the type and stage of testicular cancer, you may receive one of several treatments, or a combination.

Signs and symptoms of testicular cancer include:

• A lump or enlargement in either testicle
• A feeling of heaviness in the scrotum
• A dull ache in the abdomen or groin
• A sudden collection of fluid in the scrotum
• Pain or discomfort in a testicle or the scrotum
• Enlargement or Tenderness of the breasts
• Back pain

Cancer usually affects only one testicle.

When to see a doctor

See your doctor if you detect any pain, Swelling or lumps in your testicles or groin area, especially if these signs and symptoms last longer than two weeks.

It's not clear what causes testicular cancer in most cases.

Doctors know that testicular cancer occurs when healthy cells in a testicle become altered. Healthy cells grow and divide in an orderly way to keep your body functioning normally. But sometimes some cells develop abnormalities, causing this growth to get out of control — these cancer cells continue dividing even when new cells aren't needed. The accumulating cells form a mass in the testicle.

Nearly all testicular cancers begin in the germ cells — the cells in the testicles that produce immature sperm. What causes germ cells to become abnormal and develop into cancer isn't known.

Although the incidence of testicular cancer has risen in recent years, more than 95 percent of cases can be cured. Treatment is more likely to be successful when testicular cancer is found early. In addition, treatment can often be less aggressive and may cause fewer side effects.

Most men with testicular cancer can be cured with surgery, radiation therapy, and/or chemotherapy. The side effects depend on the type of treatment and may be different for each person.

Seminomas and nonseminomas grow and spread differently and are treated differently. Nonseminomas tend to grow and spread more quickly; seminomas are more sensitive to radiation. If the tumor contains both seminoma and nonseminoma cells, it is treated as a nonseminoma. Treatment also depends on the stage of the cancer, the patient's age and general health, and other factors. Treatment is often provided by a team of specialists, which may include a urologist (a surgeon who specializes in diseases of the genital and urinary systems), a medical oncologist, and a radiation oncologist.

The three types of standard treatment are described below.

• Surgery to remove the testicle through an incision in the groin is called a radical inguinal orchiectomy. Men may be concerned that losing a testicle will affect their ability to have sexual intercourse or make them sterile (unable to produce children). However, a man with one healthy testicle can still have a normal erection and produce sperm. Therefore, an operation to remove one testicle does not make a man impotent (unable to have an erection) and seldom interferes with fertility (the ability to produce children). For cosmetic purposes, men can have a prosthesis (an artificial testicle) placed in the scrotum at the time of their orchiectomy or at any time afterward. Some of the lymph nodes located deep in the abdomen may also be removed (lymph node dissection). This type of surgery does not usually change a man's ability to have an erection or an orgasm, but it can cause problems with fertility if it interferes with ejaculation. Patients may wish to talk with their doctor about the possibility of removing the lymph nodes using a special nerve-sparing surgical technique that may preserve the ability to ejaculate normally.
• Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells and shrink tumors. It is a local therapy, meaning that it affects cancer cells only in the treated areas. External radiation (from a machine outside the body), aimed at the lymph nodes in the abdomen, is used to treat seminomas. It is usually given after surgery. Because nonseminomas are less sensitive to radiation, men with this type of cancer usually do not undergo radiation therapy. Radiation therapy affects normal as well as cancerous cells. The side effects of radiation therapy depend mainly on the treatment dose. Common side effects include fatigue, skin changes at the site where the treatment is given, loss of appetite, nausea, and diarrhea. Radiation therapy interferes with sperm production, but many patients regain their fertility over a period of 1 to 2 years.
• Chemotherapy is the use of anticancer drugs to kill cancer cells. When chemotherapy is given to testicular cancer patients, it is usually given as adjuvant therapy (after surgery) to destroy cancerous cells that may remain in the body. Chemotherapy may also be the initial treatment if the cancer is advanced; that is, if it has spread outside the testicle at the time of the diagnosis. Most anticancer drugs are given by injection into a vein. Chemotherapy is a systemic therapy, meaning drugs travel through the bloodstream and affect normal as well as cancerous cells throughout the body. The side effects depend largely on the specific drugs and the doses. Common side effects include nausea, hair loss, fatigue, diarrhea, vomiting, fever, chills, coughing/shortness of breath, mouth sores, or skin rash. Other side effects include dizziness, numbness, loss of reflexes, or difficulty hearing. Some anticancer drugs also interfere with sperm production. Although the reduction in sperm count is permanent for some patients, many others recover their fertility. Some men with advanced or recurrent testicular cancer may undergo treatment with very high doses of chemotherapy. These high doses of chemotherapy kill cancer cells, but they also destroy the bone marrow, which makes and stores blood cells. Such treatment can be given only if patients undergo a stem cell or bone marrow transplant. In a transplant, bone marrow stem cells or stem cells collected from the bloodstream are removed from the patient before chemotherapy is administered. These cells are frozen temporarily and then thawed and returned to the patient through a needle (like a blood transfusion) after the high-dose chemotherapy has been administered.

Men with testicular cancer should discuss their concerns about sexual function and fertility with their doctor. It is important to know that men with testicular cancer often have fertility problems even before their cancer is treated. If a man has pre-existing fertility problems, or if he is to have treatment that might lead to infertility, he may want to ask the doctor about sperm banking (freezing sperm before treatment for use in the future). This procedure allows some men to have children even if the treatment causes loss of fertility.

Factors that may increase your risk of testicular cancer include:

• An undescended testicle (cryptorchidism). The testes form in the abdominal area during fetal development and usually descend into the scrotum before birth. Men who have a testicle that never descended are at greater risk of testicular cancer than are men whose testicles descended normally. The risk remains elevated even if the testicle has been surgically relocated to the scrotum.

  Still, the majority of men who develop testicular cancer don't have a history of undescended testicles.

• Abnormal testicle development. Conditions that cause testicles to develop abnormally, such as Klinefelter syndrome, may increase your risk of testicular cancer.
• Family history. If family members have had testicular cancer, you may have an increased risk.
• Age. Testicular cancer affects teens and younger men, particularly those between ages 15 and 35. However, it can occur at any age.
• Race. Testicular cancer is more common in white men than in men.