Radiofrequency Catheter Ablation (RFA)
RFA is
used to treat cancer and many other
medical problems throughout the body
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The Role of RFA in Treating
Cancer
About Catheter Ablation and
RFA
Ablation is a medical term that refers to any
procedure performed to destroy diseased or
damaged tissue in the body. Catheter ablation is
a technique in which a thin tube, or catheter, is
inserted through the skin or threaded through the
blood vessels to the site of disease. Extreme
heat or cold, alcohol, chemotherapy drugs or
other therapies are delivered through the
catheter to the diseased tissue.
RFA treats disease with heat, a technique
preferred by many cancer experts because it can
reliably destroy a small, targeted area of tissue
without healthy affecting structures beyond the
treatment site. With RFA, the doctor can pinpoint
target areas with accuracy and monitor and
control the temperature of heat therapy.
Doctors Who Perform RFA
RFA and
other catheter ablation procedures often
are performed without surgery by
interventional radiologists. These
physicians specialize in the use of
X-rays and other techniques such as
ultrasound, computed tomography (CT) and
magnetic resonance (MR) to see inside the
body without surgery. Flexible thin tubes
(catheters) are inserted through skin or
blood vessels and guided to the treatment
site.
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Interventional
radiologists treat a liver tumor with
RFA. A video monitor displays real-time
images of the treatment-in-progress.
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Miniature instruments can be inserted through
the tube to perform a variety of treatments that
otherwise could only be performed with more
invasive open surgical procedures.*
*Catheter ablation also can
be performed by surgeons as a
surgical procedure called
intra-operative catheter
ablation. There are a number of
differences between surgery and
interventional radiology (IR). IR
treatment tools are usually
inserted through a small nick in
the skin. There are no surgical
incisions, no stitches and no
scars. General anesthesia is not
needed for many IR procedures,
and in most cases they are less
painful and have fewer risks and
complications than surgery. Most
conditions treated with IR can be
done in an outpatient setting, or
require hospitalization for only
a brief time. Patients treated
with IR can expect shorter
hospital stays – and faster
recoveries – than surgical
patients. Many people resume
normal activities within a few
days after RFA or other IR
procedures.
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About RFA
Procedures
The safety and effectiveness of RFA is well
known and the technology has been approved by the
Food and Drug Administration (FDA). Countless
patients with a variety of medical problems have
been treated with the technique. RFA has been
used for many years to treat painful bone
growths, destroy nerve fibers and relieve chronic
pain, remove small growths from the skin and stop
excessive bleeding during surgery. More recently,
the technique has become a standard treatment for
some heart rhythm disorders and inoperable liver
tumors. Many ongoing studies are testing RFA as a
therapy for various types of cancer and disease.
The heat generated in
tissues treated with RF energy causes
permanent damage to proteins that are
necessary to life, and the cancer or
other diseased cells die
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In RFA, energy is delivered
through a metal tube (probe) inserted into tumors
or other tissues. When the probe is in place,
metal prongs open out to extend the reach of the
therapy. RF energy causes atoms in the cells to
vibrate and create friction. This generates heat
(up to 100o C) and leads to the death of the
cells.
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To
treat cancer with RFA, a metal probe is
inserted through the skin and into the
tumor.
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Prongs
pop open to deliver RF energy, which
generates heat that kills cancer cells.
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RFA may be performed with general anesthesia,
or with light sedation (medications to make the
patient drowsy and relaxed). If general
anesthesia is not used, a local anesthetic is
given to numb the skin and underlying tissues.
Most patients do not experience pain or serious
side effects during or after the procedure.
About RF Energy
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RF is a
form of electromagnetic (EM) energy,
which is formed from waves of electric
and magnetic energy moving together (or
radiating) through space at the speed of
light. This type of energy is a constant
presence in our natural environment
– visible light, radio waves and
microwaves, for example, are forms of EM
energy.
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This drawing
simulates an RFA probe inserted through
the skin and into a tumor. RF energy is
directed through the tube from a small
generator, and sensors record the
temperature of the treated tissue.
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Electromagnetic energy is
“non-ionizing” – which means it is
not strong enough to ionize atoms and molecules
in cells (ions are electrically charged particles
that, like magnets, are drawn toward positive or
negative poles). “Ionizing” radiation
(e.g. gamma rays and x-rays), on the other hand,
affect the chemical makeup of cells, and alter
their genetic code.
Radiofrequency energy
is safer than many cancer therapies
because it is absorbed by living tissues
as simple heat. Regardless of the heat
source, cells will die when they reach a
certain temperature. But RF energy and
the heat it generates do not alter the
basic chemical structure of cells.
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After RFA, computed tomography
(CT) magnetic resonance (MR) or other images are
taken to be certain that the treatment has been
effective. If all diseased tissue has not been
destroyed, RFA usually can be repeated. During
the first week after treatment, the dead tumor
will seem to have “grown” in size. Over
time, the dead tissue shrinks or disappears
altogether as it is gradually absorbed and
excreted like other waste products in the body.
BEFORE |
AFTER |
A LIVER TUMOR TREATED WITH
RFA
Dead tissue appears
larger and darker than the living tumor.
Over time, the tumor shrinks as the body
absorbs and excretes dead cells
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