Thermal Liquid Biopsy (TLB) is based on Differential Scanning Calorimetry (DSC, calorimetric thermogram analysis of serum samples) as a new clinical approach for diagnostic assessment of lung cancer patients. DSC is highly sensitive and it studies the unfolding transitions in proteins by thermal denaturation. The DSC profile of blood serum has been previously proposed as a novel approach for diagnosis and monitoring several diseases. Our main objective is to determine the TLB capacity to differentiate between Healthy Controls (HC) and Lung Cancer Patients (LCP).
Blood samples from HC and LCP were analyzed with a high sensitivity microcalorimeter VP-DSC (MicroCal-Malvern). The data were processed by Origin 7 software. Thermograms acquired were analyzed with a multiparametric method developed by our research group, procuring some indicators to interpret the results. The Area Under the Curve (AUC) was analyzed and the Youden’s Index obtained from ROC curves, allowing to construct the contingency tables. Odds Ratio (OR) was also calculated by binary logistic regression.
117 samples from LCP (Average age 64.6±8.7, 83.0% men) stage distribution (II: 5.2%, III: 25.9%; IV: 69.0%), smoking status (63.8% smoking, 6.5% non-smoking) histology distribution (37.1% Adenocarcinoma, 28.4% Squamous, 30.2% small cell) compared to 123 HC from a blood bank with homogeneous distribution. 10 out of 28 parameters of our multiparametric method showed statistical differences between HC and LCP. After developing ROC curves, AUC higher than 0.75 were observed in these 10 parameters, exceeding 0.85 in 3 of them. The Youden’s index was calculated for all, finding sensitivity and specificity values higher than 75.0-90.0% (for the best parameter both were more than 85.0%). Comparing HC to LCP, we calculated OR obtaining 10 parameters over 10, showing a high positive association between clinical parameters and DSC results.
High positive association between clinical groups and TLB parameters offers advantages over current diagnosis techniques (CT imaging), providing a powerful diagnostic approach with a minimally-invasive, low-risk, low-cost clinical test for LCP. Future promising applications, such as screening programs, could be developed from TLB.
Clinical trial identification
Legal entity responsible for the study
Instituto Investigación Sanitaria de Aragón (ISS).
Institute Carlos III (Spain).
All authors have declared no conflicts of interest.