KIT exon 9 GIST has shorter PFS on imatinib 400 mg vs exon 11. Imatinib 800 mg/day (split...
Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.
| ID | BMA-KIT-EXON9-GIST |
|---|---|
| Type | Actionability |
| Status | reviewed 2026-04-27 | pending_clinical_signoff | actionability review required |
| Diseases | DIS-GIST |
| Sources | SRC-CIVIC SRC-IRIS-OBRIEN-2003 SRC-NCCN-MELANOMA-2025 |
Actionability Facts
| Biomarker | BIO-KIT |
|---|---|
| Variant | exon 9 insertion (extracellular domain — ~10% GIST, predominantly small bowel) |
| Disease | DIS-GIST |
| ESCAT tier | IB |
| Recommended combinations | imatinib 800 mg/day split BID (1L advanced/metastatic exon 9) |
| Contraindicated monotherapy | imatinib 400 mg/day as 1L for exon 9 (inferior PFS — escalate to 800 mg) |
| Evidence summary | KIT exon 9 GIST has shorter PFS on imatinib 400 mg vs exon 11. Imatinib 800 mg/day (split 400 mg BID) improves PFS and OS vs 400 mg in this genotype (EORTC-62005 / MetaGIST meta-analysis, Gastrointest Stromal Tumor Meta-Analysis 2010). High dose is standard 1L for exon 9. |
Notes
ESCAT IB. OncoKB Level 1. Source-gap as DIS-GIST. Adjuvant strategy in high-risk resected exon-9 GIST less established — extended- duration imatinib often considered. Exon 9 GIST predominantly small-bowel primary; extra-gastric origin should prompt KIT exon 9 testing if not already done.
Used By
No reverse references found in the YAML corpus.