Salivary Biomarkers for Non-small Cell Lung Cancer Detection

Consecutive eligible patients presenting to the study institutions and associated clinics will be enrolled. Inclusion and exclusion criteria are detailed separately in the section on eligibility. The target enrollment population listed in the study design section provides a greater than 85% power to achieve the pre-specified goal for the sensitivity and specificity of the pre-specified model. Saliva will be collected in vials pre filled with mRNA stabilizer. Seven mRNA biomarkers (BRAF, CCNI, EGRF, FGF19, FRS2, GREB1, and LZTS1) will be measured in a central laboratory by quantitative PCR with the laboratory personnel blinded to the patient diagnosis. The primary outcome is the validation of a pre-specified multi-marker model. This pre-specified model incorporates 3 of the cancer genes and the housekeeping gene. The model will be validated based on the sum of sensitivity and specificity exceeding 1.3 with the lower limit of the 95% confidence interval exceeding 1.0. A secondary endpoint is the development of new multi-maker models with potential improved performance. These new models will be developed by logistic regression and compared with the pre-specified model based on the area under the receiver operating characteristic curve and the maximum sum of sensitivity and specificity. Individual candidate biomarkers will also be validated based on a statistically significant up-regulation in cancer patients compared with controls. Potential new housekeeping genes will be evaluated based on their equivalence in cancer and control as well as their performance in multi-marker models in comparison with the pre-specified housekeeping gene which is GADPH..