I
have also been concerned about the mutations that are occurring in
the tumors. My understanding is that when cells turn cancerous, the
proofreading of the DNA when cells divide is damaged so that copying
errors, a kind of mutation, become more frequent. I suppose many of
these errors may kill the cells before they can grow, but as in
evolution, some persist and reproduce. Some of these mutations give
the cells the ability to grow and develop into well functioning
tumors by acquiring the capacity to develop needed blood vessels to
provide food to the cells and the ability to avoid detection by the
immune system, for example. If pemetrexed takes out some or most of
the cells that are undergoing cell division, then it may be removing
some of the cells that are of benefit to the cancerous tissue and
harmful to me. Ultimately the cells may acquire the ability to
neutralize pemetrexed, but until that time, the drug can help keep
the tumor-positive mutations from taking hold.
Taken
all together, my oncologist wanted me to go back on chemo, and I
agreed. They arranged for me to get back into a chemo chair in the
infusion center today, and I received my first new round of
pemetrexed. I'll be getting chemo every three weeks now and will
continue until it stops working, or until there are better options
available (for example, a drug that unmasks cancer cells so the
immune system can find and kill them).
Luckily,
the side effects of pemetrexed are not horrible, mostly a few days of
fatigue, but it is something of an inconvenience and limits our
flexibility.
What It's Like in the Chemo Chair
I'm
not sure I've ever written about the process of getting pemetrexed,
so I thought I'd write a description today in case anyone would find
it interesting.
After
checking in at the desk, I go to the waiting area while I wait
my turn. They have a good selection of donated magazine there, and
look for something interesting to read. Then an assistant comes in and takes me
back to my chair. The chairs are like large recliners, and are in
cubicles separated by walls or curtains and face a wall of
windows that look out on the hospital and the mountains beyond. The
cubicle has chairs for visitors, a table, a TV, and more magazines.
Then
the nurse comes in and we begin. She (always been a woman) verifies my
identity and ask questions about my current health that she enters
into a computer on a rolling stand. They have to calculate how much
pemetrexed I need based on my weight and height, and today I had to
have my height measured for this year, and it has to be witnessed by
two people.
She
then accesses the port in my chest and attaches it to a bag of
saline, and she also attaches a bag of Kytril, an anti-nausea drug,
that infuses for ten minutes. In the meantime, the oncology pharmacy is preparing my pemetrexed
infusion based on my weight and height. When it is ready, she
returns with the drug which is shrouded in a brown plastic bag, and
with another nurse they verify who I am, what my patient number is,
and what medicine I'm getting. Then the infusion begins and lasts
for 10 minutes. She deactivates my port, and I am ready to go.
Most
of the time is taken up sitting in the waiting room and waiting for
my pemetrexed to formulated. I sit back in the recliner, and I
always find something to read. Today I found a copy of Science
magazine in the room and had the pleasant surprise of reading an
article about the domestication of the dog that quoted Greger Larson,
the son of our friends Roger and Jane Larson.
I
don't typically like to drive after chemo (even though it does not
seem to have any affect on me), so Jana goes shopping while I'm in
the chair. Today we went to Schlotzky's for one of their good
sandwiches on the way home.
