MONDAY, April 4 (HealthDay News) -- Preliminary research suggests that a blood test could offer evidence that a nonsmoker has lung cancer, potentially giving doctors a new diagnostic tool.

About one in four people who develop lung cancer have never smoked. This test could be used to find indications of the disease in patients whose chest scans show signs of potential trouble, investigator Charlie Birse, associate director of product development at Celera Corp., said in a news release from the American Association for Cancer Research.

The test "would allow these imaging tests to be further evaluated and provide a degree of certainty in diagnosis," Birse explained.

The researchers came to their conclusions after testing more than 600 samples in search of "biomarkers" that would indicate the presence of cancer. Once they found biomarkers that seemed promising, they ran the tests on samples of 80 people who had never smoked, including 40 with lung cancer and 40 who did not have the disease. The people in both groups were matched for age and gender.

The biomarkers successfully indicated cancer 83 percent of the time, the study authors said.

The study's sample size is small, cautioned Dr. Edward S. Kim, chief of the section of head and neck medical oncology at University of Texas M.D. Anderson Cancer Center, who was not part of the study team.

Overall, though, it's important to find ways to detect lung cancer that aren't invasive, he said. "CT scans for screening will be added this summer, but not much else has demonstrated any benefit."

The findings were to be released Monday at the annual meeting of the American Association for Cancer Research in Orlando, Fla.

Because this research was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

More information

For more on risk factors for lung cancer, visit the U.S. Centers for Disease Control and Prevention.