|
Liver cancer backgrounder
Causes: Hepatocellular
carcinoma (HCC) is usually brought on by chronic
liver disease or viral infections, namely Hepatitis
B or C.
Diagnosis: There are
hardly any symptoms in the early stages. "It's
a question of 'if you think of it, you'll find
it'," says Dr Sherman. "Diagnosis is made by radiology,
it doesn't necessarily require a biopsy."
Mortality: HCC is the
third most common cause of cancer death worldwide.
Most patients die within a year of diagnosis.
Prevalence: In North
America, HCC accounts for less than 1% of all
cancers, while in Africa, Southeast Asia and China,
it can be almost half of all cancers. "In the
Western world, where all these studies are initiated,
liver cancer has not been perceived as a major
problem," Dr Sherman says. "That's changing now,
because it is more frequent than before."
|
At long last, a treatment for advanced
liver cancer that actually works. Sorafenib, a drug
indicated for kidney cancer, bumps up survival rates
of patients with advanced hepatocellular carcinoma (HCC)
by 44%, according to a study in the June 20 supplement
of the Journal of Clinical Oncology. That translates
to an extra three months to live, not bad considering
there's currently no effective treatment for this unfortunate
population. The results were so positive that the trial
was stopped early so the placebo controls could receive
the medication.
FIRST
IN LINE
"The kind of patients included in the sorafenib study
have only experimental treatment available to them,"
explains Dr Morris Sherman, HCC specialist at the Toronto
General Hospital and head of the Canadian Liver Foundation
Medical Advisory Committee. "There's no effective treatment
available at this stage of the disease." Chemotherapy
isn't a viable option as it's only effective early on
in the disease.
The Sorafenib Hepatocellular Carcinoma
Assessment Randomized Protocol (SHARP) trial, which
was also presented at the American Society of Clinical
Oncologists meeting on June 4 in Chicago, included 602
patients at the advanced stage of the disease.
There's a striking delay in disease
progression with sorafenib, according to lead author
Dr Josep Llovet of the Hospital Clinic of Barcelona.
This establishes it as a first-line treatment for these
patients, he concludes.
ONE-TWO
PUNCH
The drug has a double action effect on liver cancer
cells. Targeting malignant cells, it inhibits tumour
cell growth and suppresses vascularization of the tumour.
The only major side effects observed were diarrhea and
hand-foot skin reactions.
"There have been only two large
scale studies so far for liver cancer," says Dr Sherman.
"The first drug was safe to test in patients with advanced
liver cancer, but not effective. Sorafenib is the first
drug that didn't have any major liver-related side effects
and produced positive results."
In fact, the most widely used drug
at the moment, doxorubicin, has only one trial to back
it up and is known to produce fatal complications.
GOLD
STANDARD
Dr Llovet believes his study will set the standard for
future liver cancer clinical trials. There's even a
suggestion that sorafenib may be studied in patients
with more compromised liver function, given its relative
safety.
The drug is being tested for potential
benefits in other types of cancers, but one major issue
remains: the cost. While currently an accepted treatment
for kidney cancer and expected to be shortly approved
for liver cancer, how well it is reaching those most
in need of it is another matter entirely.
"It costs $70,000 for one year
of treatment," notes Dr Sherman with some alarm. "Even
if it is approved, it may not be covered. So far it's
not covered for kidney cancer. The improvement in survival
is not huge, so it may not be considered worth it to
fund the drug for three extra months of life."
|
