Non-invasive approaches for lung cancer diagnosis

Lung cancer is the leading cause of cancer-related deaths worldwide. The case-fatality rate of lung cancer remains exceptionally high at 95% despite numerous medical advancements in therapeutic strategies in the last decades. However, patients diagnosed at Stage I are commonly curable and have a 5-year survival rate of 50–80%. Unfortunately, delayed diagnosis of lung cancer has been unavoidable and is an important factor in the overall outcome of treatment. Accordingly, screening of high-risk individuals is likely to have hugely beneficial outcomes for patient survival. Current screening approaches include low-dose computed tomography and chest X-ray. Recently, alternative approaches for lung cancer screening have been developed including analysis of biomarkers, including DNA, RNA, proteins, and antibodies in blood, sputum, bronchoalveolar lavage (BAL), and breath. Biomarker analysis would also provide critical information regarding tumor growth pattern, cells of origin of tumor, subtype of lung cancer, and/or drug metabolism as well as monitor patient prognosis. Novel non-invasive lung cancer diagnostic strategies could improve and complement the success of CT-scan and chest X-ray.