Soluble sPD-L1 and serum amyloid A1 as potential biomarkers for lung cancer

<jats:title>Summary</jats:title><jats:sec id="j_jomb-2018-0036_s_006"><jats:title>Background</jats:title><jats:p>The objective of this prospective study was to evaluate whether soluble programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) and serum amyloid A1 (SAA1) are potential diagnostic, predictive or prognostic biomarkers in lung cancer.</jats:p></jats:sec><jats:sec id="j_jomb-2018-0036_s_007"><jats:title>Methods</jats:title><jats:p>Lung cancer patients (n=115) with advanced metastatic disease, 101 with non-small cell lung cancer, NSCLC (77 EGFR wild-type NSCLC patients on chemotherapy, 15 EGFR mutation positive adenocarcinoma patients, 9 patients with mPD-L1 Expression ≥50% NSCLC – responders to immunotherapy), and 14 patients with small cell lung cancer (SCLC) were examined. ELISA method was used to determine sPD-L1 and SAA1 concentrations in patients’ plasma.</jats:p></jats:sec><jats:sec id="j_jomb-2018-0036_s_008"><jats:title>Results</jats:title><jats:p>Significantly higher blood concentrations of sPD-L1 and SAA1 were noted in lung cancer patients compared with a healthy control group. In PD-L1+ NSCLC patients, a significantly higher sPD-L1 level was noticed compared to any other lung cancer subgroup, as well as the highest average SAA1 value compared to other subgroups.</jats:p></jats:sec><jats:sec id="j_jomb-2018-0036_s_009"><jats:title>Conclusions</jats:title><jats:p>It seems that sPD-1/PD-L1 might be a potential biomarker, prognostic and/ or predictive, particularly in patients treated with immunotherapy. Serum amyloid A1 has potential to act as a good predictor of patients’ survival, as well as a biomarker of a more advanced disease, with possibly good capability to predict the course of disease measured at different time points.</jats:p></jats:sec>