Different efficacy of tyrosine kinase inhibitors by KIT and PGFRA mutations identified in circulating tumor DNA for the treatment of refractory gastrointestinal stromal tumors

Circulating tumor DNA (ctDNA) analysis may improve therapeutic decision-making for advanced gastrointestinal stromal tumors (GISTs). A pooled analysis of SCRUM-Japan studies found ctDNA in 72.7% of patients, with positivity linked to prior treatment and progressive disease. ctDNA-positive patients had shorter progression-free survival (PFS) than ctDNA-negative ones. Genotyping revealed complex KIT mutations, and ctDNA-matched tyrosine kinase inhibitors (TKIs) significantly improved PFS. ctDNA analysis offers valuable insights into disease status and treatment optimization for advanced GIST.