HUMAN BIOLOGY

reprodUCtIVe systeMs 325

examine each testicle separately after a warm bath or

shower (when the scrotum is relaxed). The testis should be

rolled gently between the thumb and forefinger to check

for any unusual lump, enlargement, or hardening (Figure

16.21A). Because the epididymis may be confused with a

lump, the important thing is to compare the two testes. A

lump may not be painful, but only a physician can rule out

the possibility of disease. Surgery is the usual treatment,

and the success rate is high when the cancer is caught

before it can spread.

Prostate cancer is second only to lung cancer in caus-

ing cancer deaths in men. There are no definite risk factors

other than having a family history of the disease. Symp-

toms include various urinary problems, although these can

also signal simply a noncancerous enlarged prostate. For

men over 40, an annual digital rectal examination, which

enables a physician to feel the prostate, is the first step

in detecting unusual lumps. A physician who suspects

cancer may order the PSA blood test, which can detect

suspiciously large amounts of that tumor marker. Depend-

ing on the results of these two tests, the next step may be

a biopsy—removing a small tissue sample for microscopic

analysis. Radiation therapy is sometimes used to kill can-

cerous tumors that have not spread beyond the prostate

(Figure 16.21B). The cure rate for prostate tumors detected

before they have spread is over 90 percent.

Many prostate cancers grow slowly and cause few prob-

lems. In such cases a physician may recommend simply

monitoring the tumor for worrisome changes.

Uterine and ovarian cancer affect women

Cancers of the uterus most often affect the endometrium
(uterine lining) and the cervix. Various types are treated by
surgery, radiation, or both. The incidence of uterine cancers
is falling, in part because precancerous phases of cervical
cancer can be easily detected by the Pap smear that is part
of a routine gynecological examination. The risk factors for
cervical cancer include having many sex partners, early age
of first intercourse, cigarette smoking, and genital warts
(Section 16.10). Endometrial cancer is more common dur-
ing and after menopause.
Ovarian cancer is often lethal because its chief
symptom, an enlarged abdomen, doesn’t show up until
the cancer is advanced and has spread. The first sign may
be abnormal vaginal bleeding or abdominal discomfort.
Risk factors include family history of the disease, having
breast cancer, and not bearing children. Surgery to remove
the ovaries and other affected tissue is the usual first step
in treatment. Patients often also receive chemotherapy,
which is moderately successful, especially in early stages
of the disease.

Testicular and prostate cancer affect men

Several thousand cases of testicular cancer are diag-
nosed annually in the United States. In early stages this
cancer is painless. However, it can spread to lymph nodes
in a man’s abdomen, chest, neck, and, eventually, his lungs.
Once a month from high school onward, men should

Figure 16.21 Men should perform testicular self-examination monthly. The instructions on this page are the method recommended

by the American Cancer Society. Do the exam when the scrotum is relaxed, as it is after a warm bath or shower. A Simply roll each

testicle between the thumb and forefinger, feeling for any lumps or thickening. As with breast lumps, most such changes are not

cancer, but a doctor must make the diagnosis. B Patient undergoing radiotherapy for prostate cancer. Guided by a grid template (black)

the surgeon is using a hollow needle to insert radiation-emitting “seeds” into the cancerous tissue. (© Cengage Learning)

A B

Antonia Reeve/Science Source

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