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

Introduction: To 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).

Methods: Of 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).

Results: Decrease 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).

Conclusions: Percent changes in serum ProGRP showed better correlation to SOD and prognostic impact than that of NSE.