Patients with metastatic gastrointestinal stromal tumor (GIST) and a confirmed KIT exon 9 mutation represent a molecularly defined subgroup for which specific first-line treatment recommendations apply.
The KIT exon 9 mutation is a recognised driver in a subset of metastatic GIST cases. This mutation has implications for first-line agent selection, and evidence-based guidance specifies a dosing approach that differs from other mutational contexts.
First-line management in this setting involves oral imatinib, initiated and maintained based on disease response and tolerability. The complete dosing schedule, continuation criteria, and full clinical algorithm are available in the structured protocol.