Ultra-sensitive baseline-informed MRD assay to predict prognosis outcomes in patients with resectable hepatocellular carcinoma.

Abstract

e16228 Background: The detection of minimal residual disease (MRD) has been shown to be a potential biomarker for the prognosis and post-surgery treatment of resectable hepatocellular carcinoma (HCC). However, the application of MRD in HCC has been limited by the traditional requirement of carrying out MRD over 30 days post-surgery, which is often incompatible with the time window for adjuvant treatment decisions. Additionally, MRD results may be impacted by post-surgery imbalances if assayed too soon after surgery. Methods: This retrospective study enrolled 255 early-stage HCC patients who received surgical resections and had complete information on relapse and survival. Matched tumor and normal tissue samples were collected at the time of surgery and plasma samples were collected as early as 7 days post-surgery. An ultra-sensitive, baseline-informed MRD assay (PredicineBEACON) was used to evaluate the correlation between peri-surgical MRD status and prognosis outcomes. Somatic mutations were identified through PredicineWES+ whole exon sequencing, and up to 50 somatic mutations were selected for the design of a patient-specific capture panel, in addition to a fixed panel of 500 actionable variants. Results: The study has completed MRD tests for 58 patients, of which 8 were called MRD positive with ≥0.005% tumor fractions. The tumor fraction proportion of MRD-positive patients ranged from 0.008% to 5.653% (median 0.315%). The relapse-free survival (RFS) and overall survival (OS) were correlated with MRD status: the median RFS of MRD-positive patients was 13.9 months compared to not reached after 44.4 months for MRD-negative patients (p = 0.1), and the median OS of MRD-positive patients was 27.2 months compared to not reached after 55.5 months for MRD-negative patients (p = 0.03). Conclusions: Our results demonstrate the feasibility of using an ultra-sensitive, baseline-informed MRD assay to detect strong correlations between MRD status and prognosis outcomes in peri-surgical plasma samples collected as early as 7 days post-surgery in resectable HCC patients. This study highlights the clinical utility of MRD testing in peri-surgical settings.