Cheek swab to detect early signs of lung cancer--study

Now, researchers have developed a new method to detect the first tell-tale signs of the deadly disease simply by examining the cells swabbed from patients' cheeks.

The new analysis technique, called partial wave spectroscopic (PWS) microscopy can detect cell features of lung cancer as small as 20 nanometers, by simply shining an optical light on samples taken from the cheek.

This method makes use of the "field effect", a biological phenomenon in which cells located some distance from the malignant or pre-malignant tumor undergo molecular changes.

The approach is so effective that it can distinguish non-cancerous patients from sick ones even if the former are lifetime smokers, or suffer from chronic obstructive pulmonary disease (COPD).

Lead author of the study, Hemant Roy a physician at the NorthShore University HealthSystems and the University of Chicago stated, "By examining the lining of the cheek with this optical technology, we have the potential to prescreen patients at high risk for lung cancer, such as those who smoke, and identify the individuals who would likely benefit from more invasive and expensive tests versus those who don't need additional tests."

Clinical trial of 135 volunteers
The researchers tested the technology in a small clinical trial.

The study involved 135 volunteers including 63 smokers with lung cancer, 37 smokers with COPD, 13 were smokers without COPD and 22 non-smokers.

As a part of the study, the inside of the patients’ mouth was swapped and cheek cells were placed on a slide and "fixed in" with ethanol.

The cells were then optically scanned using PWS to measure the disorder strength of cell nanoarchitecture.

It has been established that an increase in the disorder strength of cells is an early predictor in the cancer process (carcinogenesis).

Findings of the study
The analysis revealed marked differences between the cheek cells of patients suffering from lung cancer than those who were free from the disease.

The disorder strength of cells in lung cancer patients was more than 50 percent greater than in smokers without cancer.

The test was equally effective in all stages of cancer, including early curable cancers.

Roy stated, "This study is important because it provides the proof of concept that a minimally intrusive, risk-stratification technique may allow us to tailor screening for lung cancer, the leading cause of cancer deaths in Americans.

"This represents a major step forward in translating biomedical optics breakthroughs for personalized screening for lung cancer."

The study was published in the journal 'Cancer Research.'