864
UNIT SIX
in contour; or a nipple that is f
attened, points in
an unusual direction, or produces a discharge. A
woman can note these changes by perForming a
monthly “breast selF-exam,” in which she lies f
at
on her back with the arm raised behind her head
and systematically Feels all parts oF each breast.
But sometimes breast cancer gives no warning—
Fatigue and Feeling ill may not occur until the dis-
ease has spread beyond the breast.
AFter ±
nding a lump, the next step is a physi-
cal exam, where a health-care provider palpates
the breast and does a mammogram, an X-ray
scan that can pinpoint the location and approxi-
mate extent oF abnormal tissue (Fig. 22C). An
ultrasound scan can distinguish between a cyst
(a f
uid-±
lled sac oF glandular tissue) and a tumor
O
ne in eight women will develop breast
cancer at some point in her liFe (table
22D). About 1% oF breast cancer cases
are in men. Breast cancer is several illnesses. As
research reveals the cellular and molecular char-
acteristics that distinguish subtypes oF the disease,
treatments old and new are being increasingly
tailored to individuals, at the time oF diagnosis.
This approach may delay disease progression and
increase survival rate, while enabling patients to
avoid drug treatments that will not work.
Warning Signs
Changes that could signal breast cancer include a
small area oF thickened tissue; a dimple; a change
(a solid mass). IF an area is suspicious, a thin nee-
dle is used to take a biopsy (sample) oF the tissue,
whose cells are scrutinized under a microscope
For the telltale characteristics oF cancer. ²urther
tests can identiFy estrogen and progesterone
receptors on the cancer cells, which is inForma-
tion used to guide treatment choices.
22.4
CLINICAL APPLICATION
Treating Breast Cancer
TABLE
22D
|
Breast Cancer Risk
By Age
Odds
By Age
Odds
25
1 in 19,608
60
1 in 24
30
1 in 2,525
65
1 in 17
35
1 in 622
70
1 in 14
40
1 in 217
75
1 in 11
45
1 in 93
80
1 in 10
50
1 in 50
85
1 in 9
55
1 in 33
95 or older
1 in 8
FIGURE 22C
Mammogram oF a breast
with a tumor (arrow).
Combined Hormone Contraceptives
Combined hormone contraceptives deliver estrogen and pro-
gestin to prevent pregnancy. Various methods are used to
administer the hormones, but all work on the same princi-
ple with about the same efF cacy, although the amounts of
the component hormones may vary. One such method is a
small fl exible chemical ring (Nuvaring®) inserted deep into
the vagina once a month, remaining in place three out of
four weeks. A plastic patch (Ortho Evra®) impregnated with
the hormones may be applied to the skin on the buttocks,
stomach, arm, or upper torso once a week for three out of
four weeks. The most commonly used method to deliver the
hormones is orally, in pill form (F
g. 22.35
d
).
Combined hormone contraceptives contain synthetic estro-
gen-like and progesterone-like chemicals. These drugs disrupt
the normal pattern of gonadotropin (±SH and LH) secretion,
preventing follicle maturation and the LH surge that triggers
ovulation. They also interfere with buildup of the uterine lin-
ing necessary for implantation of a blastocyst. One oral contra-
ceptive does not include placebo days when no hormones are
taken, and as a result, menstruation does not occur.
If used correctly, combined hormone contraceptives pre-
vent pregnancy nearly 100% of the time. However, they may
cause nausea, retention of body fl uids, increased skin pigmen-
tation, and breast tenderness. Some women, particularly those
over thirty-F ve years of age who smoke, may develop intra-
vascular blood clots, liver disorders, or high blood pressure
when using certain types of these contraceptives. The patch,
for example, has a higher amount of estrogen than other prod-
ucts and bears a warning label about the association with
blood clots.
Similar to, but different from the combined hormone
contraceptives is the “minipill,” which contains only proges-
tin. The progestin thickens the cervical mucus so the sperm
have difF culty reaching the egg. The minipill must be taken
every day at approximately the same time for maximum
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