Porth's Essentials of Pathophysiology, 4e

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Genitourinary and Reproductive Function

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Studies have linked this cancer to exposure to tar, soot, and oils. Most squamous cell cancers of the scrotum are linked to poor hygiene and chronic inflammation. Exposure to PUVA or HPV also has been associated with the disease. The mean age of presentation with the disease is 60 years, often preceded by 20 to 30 years of chronic irritation. In the early stages, cancer of the scrotum may appear as a small tumor or wartlike growth that eventually ulcer- ates. The thin scrotal wall lacks the tissue reactivity needed to block the malignant process; more than one half of the cases seen involve metastasis to the lymph nodes. Because this tumor does not respond well to chemotherapy or irradiation, the treatment includes wide local excision of the tumor with inguinal and femoral node dissection. 34 Prognosis correlates with lymph node involvement. Testicular Cancer. Testicular cancer accounts for 1% to 2% of all neoplasms in men. 35 Although relatively rare, it is the most common cause of cancer in 20- to 35-year- old males. 35 In the past, testicular cancer was a leading cause of death among men entering their most produc- tive years. Since the late 1970s, however, advances in therapy have transformed an almost invariably fatal dis- ease into one that is highly curable. Although the cause of testicular cancer is unknown, several predisposing influences may be important: crypt- orchidism, genetic factors, and disorders of testicular development. 14,15,35 The strongest association has been with cryptorchid or undescended testis. Genetic predis- position also appears to be important. Family clustering of the disorder has been described, although a well- defined pattern of inheritance has not been established. Men with disorders of testicular development, including those with Klinefelter syndrome and testicular feminiza- tion, also have a higher risk. The majority of testicular tumors are of germ cell ori- gin. 14,15 Germ cell tumors can be classified as seminomas and nonseminomas. Seminomas account for approxi- mately 50% of germ cell tumors and are most frequent in the fourth decade of life. 14,15 Seminomas tend to retain the phenotypic features of spermatogonia and are the type of germ cell tumor most likely to produce a uniform population of cells. The nonseminoma tumors include embryonal carcinoma, teratoma, choriocarcinoma, and yolk cell carcinoma derivatives. They usually contain more than one cell type and are less differentiated than seminomas. Embryonal carcinomas are the least differ- entiated of the tumors, with the capacity to differenti- ate into other nonseminomatous cell types. They occur most commonly in the 20- to 30-year-old age group. Choriocarcinoma is a rare and highly malignant form of testicular cancer that is identical to tumors that arise in placental tissue. Yolk sac tumors mimic the embryonic yolk sac histologically. They are the most common type of testicular tumors in infants and children up to 3 years of age, and in this age group have a very good progno- sis. Teratomas are composed of somatic cell types from two or more germline layers (ectoderm, mesoderm, or endoderm). They constitute less than 3% of germ cell tumors and can occur at any age from infancy to old age.

They usually behave as benign tumors in children, but contain minute foci of cancer cells in adults. Often the first sign of testicular cancer is a slight enlargement of the testicle that may be accompanied by some degree of discomfort. This may be an ache in the abdomen or groin or a sensation of dragging or heavi- ness in the scrotum. Frank pain may be experienced in the later stages, when the tumor is growing rapidly and hemorrhaging occurs. Testicular cancer can spread when the tumor may be barely palpable. Approximately 10% of men present with symptoms related to meta- static disease. 35 Signs of metastatic spread include swell- ing of the lower extremities, back pain, neck mass, cough, hemoptysis, or dizziness. Gynecomastia (breast enlargement) may result from human chorionic gonad- otropin (hCG)-producing tumors and occurs in about 5% of men with germ cell tumors. Although routine screening and monthly self-examination in young men has been recommended, studies have not shown that they improve outcomes. 35 However, men with sugges- tive signs and symptoms should be carefully evaluated to avoid delayed diagnosis or misdiagnosis. The diagnosis of testicular cancer requires a thorough urologic history and physical examination. A painless testicular mass may be cancer. Conditions that produce an intrascrotal mass similar to testicular cancer include epididymitis, orchitis, hydrocele, or hematocele. The examination for masses should include palpation of the testes and surrounding structures, transillumination of the scrotum, and abdominal palpation. Testicular ultra- sonography can be used to differentiate testicular masses. CT scans andMRI are used in assessing metastatic spread. Tumor markers that measure protein antigens pro- duced by malignant cells may provide information about the existence of a tumor and the type of tumor present. Three tumor markers are of importance in the diagno- sis and management of testicular cancer: α -fetoprotein (AFP), β -hCG, and lactic acid dehydrogenase (LDH). 14,35 α -Fetoprotein is normally present in fetal serum in high levels, but should be present in only trace amounts beyond the age of 1 year. β -Human chorionic gonado- tropin is a hormone produced by the placenta in preg- nant women, and should not be present in significant levels in the normal male. Elevated serum LDH levels, a cellular enzyme found in muscle, liver, kidneys, and brain, has been shown to correlate with the mass of tumor cells. Lactic acid dehydrogenase is often elevated in widespread, metastatic testicular cancer. The basic treatment of all testicular cancers includes orchiectomy, which is done at the time of diagnostic exploration. Depending on the histologic characteris- tics of the tumor and the clinical stage of disease, radia- tion or chemotherapy may be used after orchiectomy. Rigorous follow-up in all men with testicular cancer is necessary to detect recurrences, most of which occur within 2 years of the end of treatment. 35,36 Testicular cancer is a disease in which even recurrence is highly treatable. With appropriate treatment, the prognosis for men with testicular cancer is excellent. Even patients with more advanced disease have excellent chances for long-term survival.