00:01
Hi, today I'd like to talk about the
gynecologic care of women with breast cancer.
00:06
But before I do that, I just wanna
review some of the medications
that we use to treat
women with breast cancer
There's a whole group of medications called Selective
Estrogen Receptor Modulators or SERMs for short.
00:19
This is a class of synthetic compounds that
actually interact with the estrogen receptor.
00:25
And so depending on what tissue they are
interacting with the estrogen receptor,
they have different effects -
either agonistic or antagonistic.
00:34
And there is a different one, so first let's
review what the structure of estradiol looks like.
00:40
So 17-beta-estradiol looks like this.
00:44
While Clomiphene citrate, another
Selective Estrogen Receptor Modulator
which is used for infertility
ovulation induction looks like this.
00:53
And Tamoxifen which you probably heard
of is used to treat breast cancer,
at least Estrogen Receptor-positive
breast cancer looks like this.
01:02
So hormones and Selective Estrogen
Receptor Modulators work this way.
01:07
Hormones or the medications, the
SERMs going to the circulation,
they diffuse into a cell through the cytoplasm and
into the nucleus to bind to the estrogen receptors,
either estrogen receptor-alpha
or estrogen receptor-beta.
01:22
These receptors then interact
with the DNA within the nucleus
and change transcription - that is the
making of messenger RNA or mRNA.
01:32
The mRNA provides the message at
the ribosomes to make proteins.
01:37
So let's now talk about
breast cancer in the US
Breast cancer is the most common
noncutaneous malignancy among women
representing 4 in 10 female
cancer survivors in the US
Long term survival is
common after breast cancer
with the 5-year survival rate being
almost 90% which is very good news.
01:58
The most common malignancy that affects
women younger than 45 is breast cancer.
02:04
So after surviving breast cancer, it's important
to know how to take care of these patients.
02:10
So many patients who have
Estrogen Receptor-positive tumors
we give them Tamoxifen to downregulate
estrogen within their breast tissue.
02:19
So again, to review, Selective Estrogen Receptor
Modulators cmpete for the estrogen receptor
and blocks the growth of
ER-positive cancer cells.
02:31
They have mixed agonist
and antagonist capability
and they are most applicable
in premenopausal patients
so patients who are still
reproductively capable.
02:43
It is currently recommended that treatment
be extended from 5, now to 10 years.
02:50
Tamoxifen though does have risks.
02:52
There are increased risk of stroke, increased
risk of endometrial cancer, blood clots,
hot flushes which
is commonly called in layman's terms "hot flashes",
changes in menstruation, mood
changes and increased triglycerides
which can cause long-term
cardiovascular problems.
03:13
There are another group of drugs that we use
and those are called aromatase Inhibitors
and they are more appropriate
for the post-menopausal patient
or a woman who's already
gone through menopause.
03:24
So let's review how
Aromatase Inhibitors work.
03:27
So steroidogenesis, that is the formation
of steroids occurs with cholesterol
going down a very long pathway that leads
to androgens turning into estrogens
through aromatase which is
also abbreviated CYP19A1.
03:44
Aromatase inhibitors inhibit this enzyme
so that there is less estrogen being made
that is estrone or estradiol.
03:55
An aromatase inhibitors do have symptoms
including vaginal dryness, decreased libido,
decreased libido essentially
means decreased sexual drive.
04:08
There's increased musculoskeletal pain
and there's also increase in cholesterol
which can cause long-term
cardiovascular effects.