safe margin of normal tissue), segmental MASTEC-
TOMY(removal of the one quarter segment of the
breast that contains the tumor), simple mastec-
tomy (removal of the breast), or modified radical
mastectomy (removal of the breast and some sur-
rounding tissue along with SENTINEL LYMPH NODE
DISSECTION).
Nearly all women who have surgery for breast
cancer also receive adjuvant (follow-up) therapy,
which may include RADIATION THERAPY, CHEMOTHER-
APY, HORMONE THERAPY, or MONOCLONAL ANTIBODIES
(MABS) therapy, either singularly or in combina-
tion. These therapies also may be primary treat-
ment for later stage and recurrent breast cancers.
In the late 1990s hormone therapy and MAbs
therapy (also called biological response modifier
therapy or IMMUNOTHERAPY) became the frontrun-
ners in adjuvant therapy for HORMONE-DRIVEN CAN-
CERS—tumors sensitive to estrogen (ER+) or
progesterone (PR+)—and HER-2/neu-positive
tumors, respectively. In late 2005 the National
Comprehensive Cancer Network (NCCN) issued
revised treatment guidelines for breast cancer in
which the cancer’s hormone andher-2status are
the primary factors for deciding the type and
course of adjuvant therapy, with the traditional
practice of evaluating tumor size and the degree of
METASTASISbeing a secondary step.
Hormone therapy for breast cancer Hormone
therapy targets suppression of estrogen and pro-
gesterone in the woman’s body. Among the thera-
pies to achieve this goal are
- selective estrogen receptor modulators
(SERMs), drugs that bind with estrogen recep-
tors to keep estrogen from doing so; SERMs
have some estrogen-like qualities that help
maintain BONE DENSITYand lipid METABOLISM - estrogen receptor downregulators (ERDs),
which first bind with estrogen receptors and
then destroy them - aromatase inhibitors, which block the action of
aromatase, an enzyme that converts ANDROGENS
naturally occurring in body tissues such as fat
into estrogen
Hormone therapy for breast cancer is effective
in women who are past MENOPAUSEor who have
no ovarian function due to surgical removal of the
OVARIES(OOPHORECTOMY) or chemical suppression of
ovarian function (medications such as goserelin
and leuprolide). Blocking estrogen production cuts
off the supply of estrogen to cancer cells that
require it, preventing the cells from growing. Side
effects that may occur with hormone therapy
include JOINT PAIN, NAUSEA, DIARRHEA, HEADACHE, and
HOT FLASHES.
SERMs were the first effective hormone ther-
apy drugs (tamoxifen came on the market in the
1980s). They generally have therapeutic value for
about five years, after which their ability to bind
with estrogen receptors diminishes. Oncologists
may recommend taking a SERM for five years and
then switching to an aromatase inhibitor, which
does not appear to have time-limited usefulness.
Aromatase inhibitors and ERDs are too new in
clinical practice to know their long-term effective-
ness.HORMONE THERAPY DRUGS TO TREAT BREAST CANCER
Selective Estrogen Receptor Modulators (SERMs)
raloxifene (Evista)
tamoxifen (Nolvadex)
toremifene (Fareston)Aromatase Inhibitors
anastrazole (Arimidex)
exemestane (Aromasin)
letrozole (Femara)Estrogen Receptor Downregulators (ERDs)
fulvestrant (Faslodex)Trastuzumab (Herceptin)Trastuzumab, a mon-
oclonal antibody, specifically targets her-2recep-
tors on breast cancer cells. First produced in the
early 1970s, trastuzumab demonstrated its effec-
tiveness againsther-2positive breast cancer in the
1980s and became the cornerstone of treatment
for her-2positive metastatic breast cancer in the
1990s. Because trastuzumab so narrowly targets
breast cancer cells, it causes few side effects. How-
ever, one significant, though rare, SIDE EFFECTis
HEART FAILURE. In the first decade of the 2000s,
oncologists began administering trastuzumab for
her-2 positive stage 2, stage 3, and stage 4/metasta-
tic breast cancers along with combination
chemotherapy.252 The Reproductive System