Blood Test Spots Lung Cancer
Test Could Detect Cancer Earlier, at More Curable Stages
Oct. 2, 2006 (Istanbul, Turkey) -- A new blood test may be able to spot lung cancer in its earliest stages, when it is potentially curable, French researchers report.
The test has the potential to save millions of lives, says researcher William Jacot, MD, a cancer specialist at the Hopital Arnaud de Villeneuve in Montpellier, France.
"While it's not ready for prime time, the test would ideally be given to seemingly healthy people at high risk of lung cancer -- for example, smokers aged 45 or older," he tells WebMD. "You want to give it before symptoms develop, perhaps repeating it every six months or so."
Test Detects Protein Fingerprints
Speaking at the annual meeting of the European Society for Medical Oncology (ESMO), Jacot says the test detects proteins produced by cancer cells in the blood. Cancer cells produce different types and amounts of proteins in the blood than other cells, giving them a unique fingerprint, he explains.
For the study, Jacot analyzed blood samples from 170 people, 147 of whom had lung cancer and 23 of whom had smoking-related chronic lung disease. The test was able to identify unique protein blueprints in more than 90% of the people with lung cancer.
Need for Early TestOther researchers stress the need for such a test.
"One of the main problems with lung cancer is that we presently have no means for early detection," says Dirk Schrijvers, MD, a medical oncologist at Middelheim Hospital in Antwerp, Belgium, and chairman of the ESMO's Publication Working Group. "A blood test like this could overcome this problem."
The implications are huge, he says, given that about 2 million people worldwide -- mostly smokers -- are diagnosed with lung cancer every year.
In the U.S., the American Cancer Society estimates there will be about 174,470 new cases of lung cancer in 2006.
According to Jacot, nearly three-fourths of people with lung cancer are diagnosed only after the cancer has spread to other parts of the body. That results in a dismal outlook, with only 6% to 16% of people still living five years later.
In contrast, up to 70% of people whose cancer is caught early can expect to survive five years or more, he says.
Giannis Mountzios, MD, of the Institut Gustave Roussy in Villejuif, France, says this is one of a growing number of studies showing that identifying markers in blood can lead to earlier diagnosis and better, more targeted therapies.
His own study, also presented at the meeting, showed that people with lung cancer who have never smoked have a distinct group of molecular markers in their cells.
If confirmed, "the study suggests that nonsmokers might respond to different treatments than are given to smokers with lung cancers. It can help us to identify the right treatment for the right patient."
Jacot says he hopes his test will be validated and ready for routine use within five to 10 years.