Prognostic value of circulating cell-free DNA in association with choriocarcinoma syndrome development in patients with germ cell tumors.

Abstract

424 Background: Germ cell tumors (GCTs) represent a highly curable malignancy; however, a small portion of patients can develop choriocarcinoma syndrome (CS) connected with acute respiratory distress syndrome (ARDS) with high mortality rate shortly after the chemotherapy start. The aim of this study was to assess the prognostic value of circulating cell-free – extracellular DNA (ecDNA) in patients with GCTs and its association with CS development and outcome. Methods: This study included 23 patients with poor-prognosis GCTs treated from November 2002 to May 2018 at the National Cancer Institute in Slovakia. Pre-treatment total ecDNA, nuclear (ncDNA) and mitochondrial DNA (mtDNA) were quantified in plasma using fluorometry and real-time PCR and analyzed in association with CS development and survival. Results: Four (17%) patients developed CS and all of them died due to ARDS shortly after the chemotherapy start. Total ecDNA, but not ncDNA or mtDNA were associated with CS development. Four out of 11 (37%) patients with high plasma ecDNA developed CS compared to 0 out of 12 (0%) patients with low plasma ecDNA (p = 0.037). In univariate analysis, higher concentration of ecDNA also positively correlated with ECOG PS ≥2, metastatic lung involvement ≥50%, weight loss ≥10%, hemoglobin ≤100 g/l, and neutrophil to lymphocyte ratio ≥ 3.3 at the time of presentation. Patients with low ecDNA had significantly better PFS (HR = 0.35, 95% CI 0.11-1.17, p = 0.043) and OS (HR = 0.26, 95% CI 0.06-1.20, p = 0.032) compared to patients with high pretreatment concentration of ecDNA. Conclusions: In this study we have proved that quantitative analysis of plasma ecDNA has prognostic value for CS development in patients treated due to GCTs. Further research focused on the biology of ecDNA may help us to understand its role as a biomarker, but also a potentially treatable pathogenic factor for choriocarcinoma syndrome development.