Correlations between serial pro-gastrin-releasing peptide and neuron-specific enolase levels, and the radiological response to treatment and survival of patients with small-cell lung cancer

Abstract

IntroductionTo investigate whether decrease in the serum levels of pro-gastrin releasing peptide (ProGRP) and neuron-specific enolase (NSE) were correlated with the radiological response in patients with small-cell lung cancer (SCLC). MethodsOf the 196 patients, we retrospectively reviewed 118 patients elevated baseline levels of ProGRP and NSE prior to the initial therapy (IT) who survived for more than 1 month. The radiological response was assessed by Response Evaluation Criteria in Solid Tumors (RECIST 1.1). ResultsDecrease in the serum ProGRP was strongly correlated with the decrease of the sum of the tumor diameters (SOD) before the third course (ρ=0.50) and after the fourth course (ρ=0.42) of IT. Decrease in the serum NSE was weakly correlated with the decrease of the SOD after the fourth course (ρ=0.27), but not before the third courses (ρ=0.22). In the receiver operating characteristic (ROC) curves predicting 1-year survivors, the area under the curve (AUC) for percent changes in serum ProGRP before the third course were significantly larger than those for NSE (0.714 vs. 0.527, p=0.004). ConclusionsPercent changes in serum ProGRP showed better correlation to SOD and prognostic impact than that of NSE.