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What is involved?
First, the porfimer sodium is given intravenously (IV or into
a vein). It travels through the bloodstream to be absorbed by all cells
in the body, including both normal and cancer cells. The normal cells
get rid of most of the porfimer sodium over a couple of days. But a lot
of the drug stays in the cancer cells and in the skin cells.
Porfimer sodium alone does not destroy cancer cells. It must
be activated by light. This is done about 2 or 3 days after the drug is
given so that normal cells have a chance to get rid of it. The doctor
then directs a laser light at the area of cancer cells using a very
thin glass strand called a fiber
optic. To treat esophageal cancer or Barrett esophagus,
the fiber optic is passed down the throat through a thin, flexible tube
called an endoscope. For lung cancer treatment, the fiber optic is
passed through a bronchoscope, which is an endoscope that is designed
to reach the lung.
The laser used is a low-power light so it does not burn, and
there is little or no pain during the procedure. The light is applied
for 5 to 40 minutes, depending on the size of the tumor being treated.
Any dead tissue left in the treated area is removed about 4 or 5 days
later during endoscopy or bronchoscopy. The treatment can be repeated
if needed.
Who should not get treated with porfimer
sodium?
Porfimer sodium is not recommended for people with:
- a disease of the blood called acute intermittent porphyria
- an allergy to porphyrins
- a fistula (abnormal opening) between the windpipe and
esophagus or between a bronchus and esophagus
- a tumor eroding into a major blood vessel
Possible side effects
The major possible side effects from porfimer sodium are
photosensitivity reactions and swelling in the treated area (which may
cause pain or trouble swallowing or breathing). Other, minor side
effects are possible, too.
Photosensitivity reactions
As soon as porfimer sodium is injected into the bloodstream,
it begins to collect in the cells of the body. Some of it will stay in
the cells for several weeks. The skin and eyes are especially sensitive
to light during this time. If exposed to sunlight or other forms of
bright light, the skin can quickly become swollen, sunburned, and
blistered. It takes only a few minutes for a reaction to occur, so it
is very important to protect the eyes and skin during this time. Once
you get an injection of porfimer sodium, you should take precautions
(see below) for at least 30 days to prevent reactions. Sensitivity to
light can last as long as 3 months, but the length of time is different
with each person. If you have a reaction, call your doctor right away.
You should try to avoid bright lights and direct sunlight, but
you do not have stay in dark rooms. Some indoor light is important
because it will help to slowly break down the drug in your skin. As
this happens, your skin will become less photosensitive over time. Ask
your doctor when and how you should test your skin for
photosensitivity. This is usually done no sooner than 30 days after you
get the injection.
Taking these precautions can help prevent a photosensitivity
reaction:
- Before going to your doctor's office or hospital for
treatment, close the shades and curtains on the windows in your home.
Be sure windows and skylights are fully covered.
- Bring dark sunglasses, gloves, a wide brimmed hat, pants,
socks, shoes, and a long-sleeve shirt to wear after your appointment.
Clothing should be light in color and the fabric should be tightly
woven.
- Do not count on sunscreen to protect you. Sunscreens only
protect against ultraviolet light, so they will not prevent a
photosensitivity reaction.
- For at least 30 days after you get the injection, limit
your time outdoors, especially when the sun's rays are strongest
(between about 10AM and 2PM). When you do go outside, cover as much
skin as possible, even on cloudy days and when you are in the car.
- Try to do most daily errands after sundown.
- Do not expose your skin to reading lamps, exam lamps (such
as those used in a dentist's office), or "helmet"-type hair dryers
(such as those found in beauty salons). If you use a hand-held hair
dryer, use a low heat setting to avoid burns to your scalp.
Swelling
Swelling in the area being treated can lead to pain in the
chest or back. If the esophagus is being treated, it may lead to
narrowing (stricture) of the esophagus, which could cause problems
swallowing. Treatment of the lung could lead to trouble breathing. If
you note any of these problems, let your doctor know right away.
Other possible side effects
Side effects depend on the area of the body being treated. If
the esophagus is being treated, possible side effects include nausea,
vomiting, fever, dehydration, headache, hiccups, and fluid build-up
around the lungs. In people being treated for lung cancer, possible
side effects include shortness of breath, coughing up blood, fever,
pneumonia, and bronchitis.
If you are being treated with porfimer sodium, ask your doctor
which side effects to report right away and what phone number to call
if you have side effects after regular office hours.
Revised: 04/23/08
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