Longitudinal circulating tumor DNA analysis during treatment of locally advanced resectable gastric or gastroesophageal junction adenocarcinoma: the PLAGAST prospective biomarker study.

ABSTRACT: Patients with locally advanced resectable (LAR) gastric/gastroesophageal junction (G/GEJ) adenocarcinomas have a high recurrence risk despite pre- and post-operative treatment. In the PLAGAST prospective study (NCT02674373), we investigated the ability of circulating tumor DNA (ctDNA) to predict treatment response and improve risk stratification. Plasma samples were prospectively collected before neoadjuvant therapy (NAT), during-NAT, post-NAT, and post-surgery. The primary endpoint was recurrence-free survival (RFS), and the secondary endpoints were overall survival (OS), tumor regression grade (TRG), and pathological tumor stage. ctDNA positivity decreased over these four therapeutic timelines (69.6%, 51.2%, 26.8%, and 20%, respectively). ctDNA-positivity was associated with significantl

SUBMITTER: Zaanan A 

PROVIDER: S-EPMC12289871 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature