Blood Test for Lung Cancer in the Works
Test in Development Could Spare Patients Invasive Procedures, Researchers Say
Jan. 13, 2010 (Coronado, Calif.) -- A blood test under study to help
diagnose lung cancer looks promising, researchers reported Tuesday at a cancer
meeting in California.
If perfected, the test could help spare patients the need to undergo
invasive procedures such as biopsies when lung cancer is suspected, they
''Currently, 20% to 25% of surgeries done for suspected lung cancer turn out
to be benign diagnoses," says Steven Dubinett, MD, professor of medicine and
pathology and director of the Lung Cancer Research Program at the Jonsson
Comprehensive Cancer Center at the David Geffen School of Medicine, University
of California, Los Angeles. He is the senior author on the study, presented at
the American Association for Cancer Research-International Association for the
Study of Lung Cancer's joint conference in Coronado, Calif.
About 219,000 new cases of lung cancer were expected to be diagnosed in the
U.S. in 2009, according to the American Cancer Society, and about 159,000
deaths were expected.
According to Dubinett, about one in 500 chest X-rays shows a lung nodule of
''indeterminant significance." When that occurs, the next step is to examine
the suspicious area, with the physician ordering a biopsy or inserting a scope
into the lungs to evaluate further.
Lung Cancer Blood Test: Study Details
Building on their own previous research and that of others, Dubinett and his
colleagues assembled a panel of 40 potential lung cancer biomarkers --
substances found in the blood that can be measured and detected with blood
These biomarkers, Dubinett says, are made up of proteins thought to
contribute to lung cancer progression or whose levels may be changed as a
result of the tumor. The thinking among experts studying these biomarkers is
that they will be present in the blood of people who are in the very early
stages of lung cancer.
The researchers took blood from 90 lung cancer patients and from 56 people
at high risk for lung cancer because of a heavy smoking history who had quit
for at least a year.
They found that 33 of the 40 biomarkers were different between the lung
cancer patients and those not diagnosed with lung cancer. They found that the
panel of biomarkers was accurate in identifying lung cancer patients 88% of the
time. It also correctly identified patients who did not have lung cancer 79% of
Then they evaluated whether the markers could help detect lung cancer in
early stages -- a challenge overall in the diagnosis of lung cancer. They
compared blood samples from 31 patients with stage I lung cancer to the
patients not diagnosed. There were 21 markers different enough between stage I
cancer patients and non-cancer patients to suggest the method is sensitive
enough to detect tumors in early stages.