Jan. 20, 2010 -- Researchers say they have developed a blood test that can
spot pancreatic cancer earlier, when it is more curable.
The test uses an antibody that works like a heat-seeking missile, homing in
and attaching to cells that carry a protein called PAM4 that is present in the
vast majority of pancreatic cancers.
"This protein appears to be very specific for pancreatic cancer. It's
[rarely] found in normal tissue or other cancers," says David V. Gold, PhD, of
the Garden State Cancer Center in Belleville, N.J.
Importantly, PAM4 is also seldom detected in pancreatitis, a condition
marked by inflammation of the pancreas that is initially often difficult to
distinguish from pancreatic cancer, he says.
The antibody also shows promise for treating the disease by acting as a
carrier for radiation or drugs that can target and kill pancreatic cancer
cells, Gold says.
The findings were released today in advance of the 2010 Gastrointestinal
Cancers Symposium, being held later this week in Orlando, Fla.
Pancreatic cancer is the fourth leading cause of cancer deaths in men and
women in the U.S. More than 42,000 new cases and over 35,000 deaths are
expected in 2010 in the U.S., according to the American Cancer Society.
"This disease is a killer," Gold says. "Only 2% to 3% of patients will
survive for five years."
The reason, Gold tells WebMD, is that most patients with pancreatic cancer
are not diagnosed until the disease has spread throughout the body.
"The goal of the new test is to provide a tool for the detection of
early-stage disease," he says. If cancer is detected early, a patient's chance
of surviving five years jumps to 20%, according to Gold.
Currently, only 7% of pancreatic cancer cases are detected at an early
stage, before the cancer has spread.
The researchers first tried out the test on blood samples taken from nearly
300 people -- some of whom had pancreatic cancer, some of whom had other
cancers, including breast and lung, and some of whom were healthy.
"The test was positive in 77% of pancreatic patients, but only 5% of
patients with other forms of cancer," Gold says. "Thus we know that if the
[test] is positive, there is a large likelihood a patient has pancreatic
For the new study, the researchers evaluated the PAM4 protein test in 68
people who had pancreatic cancer surgery and 19 healthy people.
The test correctly detected 62% of very early-stage pancreatic cancers that
were still confined to the pancreas, 86% of cases that had spread only to
nearby tissue, and 91% of later-stage cancers that had spread further
throughout the body.
Overall, the test correctly identified 81% of all pancreatic cancers.