Stereotactic radiotherapy and cytokines: preliminary analysis in oligometastatic Non-Small-Cell lung cancer

Background: Cytokines have a recognized role in the physiopathology of cancer disease and could be involved also in the "abscopal effect". Aim of this work is the preliminary analysis of inflammatory mediators in patients with oligometastatic non-small-cell lung cancer (NSCLC) undergoing stereotactic radiotherapy (SRT). Materials and Methods: This was a feasibility multi-institutional study that prospectively included oligometastatic NSCLC patients undergoing SRT from June 2018 until August 2018 and healthy controls. Blood samples were collected at three different time points (1-5 days before SRT, 1-5 days after SRT and 28-35 days after SRT). A commercially available kit was used for quantitative analysis of 44 inflammation molecules. Nine patients and four healthy controls were enrolled. Results: Several cytokines (54.5%) resulted undetectable in a significant percentage of the samples and were not further analyzed. Levels of seven inflammatory molecules (bDNF, MIP-1b, PDGF-bb, PIGF-1, RANTES, SDF1-a, and bNGF) showed significant variations after SRT in the NSCLC patients cohort. Conclusion: Significant plasmatic concentration changes after SRT were reported for a relevant proportion of the evaluated molecules. The results of this study will contribute to define a selection of cytokines and chemokines that will be analyzed in a prospective trial with a larger sample of patients.