Malignant testicular tumors, which rank first in cancer deaths among men ages 20 to 35, primarily affect young to middle-aged men; they are the most common solid tumor in this group. (In children, testicular tumors are rare.) Most testicular tumors originate in gonadal cells. About 40% are seminomas— uniform, undifferentiated cells resembling primitive gonadal cells. The rest are nonseminomas—tumor cells showing various degrees of differentiation.
The prognosis varies with the cell type and disease stage. When treated with surgery and radiation, almost all patients with localized disease survive beyond 5 years.
The cause of testicular cancer isn’t known, but incidence (which peaks between ages 20 and 40) is higher in men with cryptorchidism (even when surgically corrected) and in men whose mothers used diethylstilbestrol during pregnancy. Exposure to certain chemicals, infection with human immunodeficiency virus, and a family history of testicular cancer increase risk. (Testicular cancer accounts for 1% of all cancers in men.)
Testicular cancer spreads through the lymphatic system to the para-aortic, iliac, and mediastinal lymph nodes and may metastasize to the lungs, liver, viscera, and bone.
Signs and symptoms
The first sign is usually a firm, painless, smooth testicular mass, varying in size and sometimes producing a sense of testicular heaviness. When such a tumor causes chorionic gonadotropin or estrogen production, gynecomastia and nipple tenderness may result.
In advanced stages, signs and symptoms include ureteral obstruction, abdominal mass, cough, hemoptysis, shortness of breath, weight loss, fatigue, pallor, and lethargy.