Sizing and concentration analysis of cfDNA using Biabooster technology: Results from a prospective plasma‐based collection of 77 patients with locally advanced unresectable esophageal cancer

Locally advanced esophageal carcinoma remains of poor prognosis correlated with tumor stage. Albeit liquid biopsy approach offers promising results to monitor high-risk patients in various solid tumors, the lack of specific mutation in esophageal tumor, limits the detection of circulating tumor DNA (ctDNA) with high sensitivity using sequencing-based methods. In this study, we employed a highly sensitive technology of fragmentome assay, previously validated to measure concentration and size distribution of cell-free DNA (cfDNA), to analyze plasma samples from 77 patients with esophageal carcinoma, compared to 15 healthy controls. Total cfDNA concentration was significantly higher in patients than in healthy donors (15.03 ± 1.37 vs. 5.87 ± 0.85 pg/μL, p < .0001). The difference remained significant regardless of tumor histology, location, stage, or nodal involvement and was independent from age or gender. Additionally, we observed a significant reduction in patients fragment length compared to healthy donors. The area under curve from receiver operating characteristic (ROC) of total cfDNA concentration in patients versus healthy donors was 0.86 (p-value <.0001). The threshold of 7.5 pg/μL yielded a sensitivity of 81% and a specificity of 80%. This prospective study demonstrated that blood samples from patients exhibit a greater global concentration of smaller fragments compared to healthy controls. These findings support further longitudinal evaluation to determine the predictive and prognostic value of cfDNA in locally advanced unresectable esophageal carcinoma.