Selectively increased autofluorescence at certain regions of skin may become a novel diagnostic biomarker for lung cancer

Early diagnosis can significantly enhance the 5-year survival rates of lung cancer patients, while a large majority of lung cancer patients have advanced disease at the time of diagnosis. We tested our hypothesis that increased autofluorescence (AF) of skin may become a new diagnostic biomarker for lung cancer, which has generated the following findings: First, the AF intensity of untreated lung cancer group in certain regions of skin is significantly higher than that of the healthy group and the group of benign lung diseases; second, the percentage of the people with 3 or more regions with increased green AF is 11.1%, 47.06%, and 71.80% for the healthy group, the group of benign lung disease patients, and the group of untreated lung cancer patients, respectively; and third, the AF intensity at several regions of the skin of untreated lung cancer patients is significantly lower than that of acute ischemic stroke patients. Moreover, the AF increases in lung cancer may result from oxidative stress-induced increases in the AF of keratins. Collectively, our study has indicated that lung cancer patients have significant AF increases in certain regions of their skin, which may become a novel diagnostic biomarker for the illness. This approach could be used to diagnose both lung cancer and acute ischemic stroke, since we may differentiate these diseases based on the differences in both the patterns of their AF at multiple regions and their clinical symptoms. This non-invasive diagnostic approach may significantly increase the rate of early diagnosis of lung cancer.