Background/Aim: In 2016 in the United States, 7 of 10 patients were estimated to die following lung cancer diagnosis. This is due to a lack of a reliable screening method that detects early-stage lung cancer. Our aim is to accurately detect early stage lung cancer using algorithms and protein biomarkers. Patients and Methods: A total of 1,479 human plasma samples were processed using a multiplex immunoassay platform. 82 biomarkers and 6 algorithms were explored. There were 351 NSCLC samples (90.3% Stage I, 2.3% Stage II, and 7.4% Stage III/IV). Results: We identified 33 protein biomarkers and developed a classifier using Random Forest. Our test detected early-stage Non-Small Cell Lung Cancer (NSCLC) with a 90% accuracy, 80% sensitivity, and 95% specificity in the validation set using the 33 markers. Conclusion: A specific, noninvasive, early-detection test, in combination with low-dose computed tomography, could increase survival rates and reduce false positives from screenings.According to the American Cancer Society, on a global scale, lung cancer is the leading cause of cancer-related incidence and death at 2.09 million cases and 1.76 million deaths in 2018 (1). By 2016, in the US, an estimated 538,243 living individuals were diagnosed with lung and bronchus cancer (2). An additional 228,150 new cases with an estimated 142,670 deaths are expected in 2019 (3).Lung cancer originates in the lungs, but can metastasize to other organs in the body. It is classified based on the histological profile of the tumor cell and predominantly falls into two major categories: i) small cell lung cancer (SCLC, 13%) and ii) non-small cell lung cancer (NSCLC, 84%) (3). Detection at Stage I or II for NSCLC can offer good prognosis.
Symptoms and detection.Current methods of detecting lung cancer include a chest x-ray (CXR), computed tomography (CT) scan, magnetic resonance imaging (MRI), positron emission tomography (PET) scan, sputum analysis, and lung biopsy. Despite the advancement in technology and the extensive cancer research, 57% of lung cancer patients are diagnosed only after a tumor has metastasized to a different location. Under these circumstances, there is little chance of a cure, and the 5-year survival rate is less than 6% (2). Late diagnosis of lung cancer can be attributed to: i) primarily the lack of symptoms at early-stage lung cancer (4) ii) misdiagnosis of the disease since early symptoms (persistent cough, shortness of breath, chest pain, wheezing, and hemoptysis) are often misinterpreted (5) iii) the lack of proven benefit for lung cancer screening until recently (6), and iv) cost effect and limited access to state-of-the-art detection methods in indigent populations (7).It is evident that the sooner lung cancer is diagnosed, the better the prognosis for the patient. However, only 16% of patients were diagnosed when the disease was still restricted to the lungs and even for these, only 57.4% survived 5 years (8). Based on the 2016 Cancer Statistics Review by SEER (8), the 5-year survival rate decreased to 30....
