Porth's Essentials of Pathophysiology, 4e - page 1023

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U N I T 1 1
Genitourinary and Reproductive Function
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.
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