Chemoembolization
A technique called transcatheter chemoembolization is used for some
patients with liver cancer or other types of cancer that have spread
to the liver. The procedure is a way of delivering cancer treatment
directly to a tumor through minimally-invasive means.
Although the procedure is not a cure for liver cancer, studies have
shown that 70 percent or more of patients experience improvement
and, depending on the type of cancer, may live longer. Chemoembolization
also may relieve pain and other symptoms, make patients more comfortable
and improve the quality of their lives. Another advantage is that
the procedure may be repeated multiple times.
How Chemoembolization
Works
The liver is unique because it has two blood supplies. The portal
vein provides 75% of the livers blood supply and the hepatic artery
supplies the remaining 25%. Tumors that grow in the liver typically
receive their blood supply from the hepatic artery making chemoembolization
possible. The drugs can be injected into the artery feeding the tumor
while sparing most of the healthy liver tissue that feeds from the
portal vein.
The treatment works in three ways to attack the cancer. First, because
the chemotherapy is delivered directly to the tumor and doesn't spread
throughout the body, stronger doses of cancer-killing drugs can be
administered compared to the doses used for standard systemic chemotherapy
which is injected through a vein in the arm. Secondly, the tiny particles
embolize, or block, the artery and decrease the flow of blood to
the tumor causing it to shrink. Finally, by blocking the artery,
the particles help contain the chemotherapy keeping it in direct
contact of the tumor for a longer period of time—in some cases
as long as a month.
This technique also may reduce some of the side effects of standard
chemotherapy because the drugs are trapped in the liver instead of
circulating throughout the body.
Chemoembolization |
How Is The Procedure
Performed?
An angiogram, a real-time X-ray that highlights where blood flows,
is performed to help the interventional radiologist look in the
liver at the tumor without the need for an open incision. The interventional
radiologist uses the x-ray images on the TV monitors to insert
the catheter (which is like a piece of spaghetti) through a small
nick in the skin at the groin and guide it through the artery that
feeds the tumor. In a separate procedure a combination of
chemotherapy drugs and tiny particles, as small as grains of sand,
are then injected directly into the tumor.
At the end of the procedure, the catheter is removed and pressure
is applied to the entry point to prevent bleeding and a band-aid
is applied. Patients remain in bed for six to eight hours and leave
the hospital within two days.
Chemoembolization can be performed repeatedly on a patient. Typically,
patients wait ten to twelve months between treatments. This procedure
can also be used in conjunction with other cancer therapies. Chemoembolization
may not be appropriate for patients who have blockages of the veins
that supply blood to the liver, cirrhosis of the liver or blockage
of the bile ducts.
What Will I Experience
After The Procedure?
After the procedure, you will receive prescriptions for oral antibiotics,
pain, and nausea. Once home, you may experience fevers for up to
a week. For the first two weeks, fatigue and loss of appetite are
common. These are all signs of a normal recovery. However, if your
fever suddenly becomes higher or your pain changes in intensity
or character, contact your physician.
Although a majority of patients can resume their normal activities
within a week, most are back to their usual state of health in about
one month. Throughout this time it's important to let your physician
know how your recovery is progressing.
Eventually, you will get a follow-up CT or MRI scan, as well as
blood tests, to determine the size of the treated tumor and how well
the chemoembolization worked. CT and MRI scans will continue every
three months thereafter to determine how much the tumor ultimately
shrunk.
Benefits vs. Risks
Benefits:
- Chemoembolization can stop liver tumors from growing or cause
them to shrink in 2/3 of cases treated. This benefit, on average,
lasts 10-14 months.
- Chemoembolization can be used in conjunction with other cancer
treatments including tumor ablation, radiation and chemotherapy.
- Most patients don't die from the spread of cancer if it is confined
to the liver, but rather from liver failure caused by the tumors
growth. Chemoembolization can help prevent the growth of a tumor,
preserving liver function and a relatively normal quality of life.
- Two randomized controlled trials published in 2002 showed improved
survival in patients with hepatoma (primary liver cancer) after
chemoembolization compared to supportive care alone.
Risks:
- Embolus (tiny particles) can lodge in the wrong place and deprive
normal tissue of its blood supply.
- Even if antibiotics are given, there is always a risk of infection
after embolization.
- There is a risk of an allergic reaction to the dye used in the
angiography x-ray.
- There is a risk of kidney damage in patients with diabetes or
other pre-existing kidney disease due to the angiography.
- Nausea, hair loss, decreases in white blood cells and platelets,
and anemia may occur due to the chemotherapy drug.
- After 1 in 20 procedures, serious complications occur and typically
include liver infection or damage to the liver. Liver failure is
usually the cause of the 1 in 100 deaths related to this procedure.