Prognosis and predictive value of KIT exon 11 deletion in GISTs

Br J Cancer. 2009 Jul 7;101(1):7-11. doi: 10.1038/sj.bjc.6605117. Epub 2009 Jun 16.


Background: KIT exon 11 mutations are observed in 60% of gastrointestinal stromal tumours (GIST). Exon 11 codes for residues Tyr568 and Tyr570, which play a major role in signal transduction and degradation of KIT. Our aim was to compare the outcome of patients with deletion of both Tyr568-570 (delTyr) and the most frequent deletion delWK557-558 (delWK).

Methods: Pathology and clinical characteristics of 68 patients with delTyr (n=26) or delWK (n=42) were reviewed and compared.

Results: GISTs with delTyr were more frequently extragastric than those with delWK (69 vs 26%, P<0.0005). After curative surgery, median relapse-free survival were 10.8 and 11.1 months for patients with delTyr (n=14) and delWK (n=29), respectively (P=0.92). All patients treated with imatinib for a non-resectable or metastatic GIST had an objective response (n=15) or a stable disease (n=21) as best response, regardless of mutation. Median progression-free survival with imatinib were 21.9 and 18.9 months for patients with GIST with delTyr (n=14) and delWK (n=22), respectively (P=0.43).

Conclusion: In this large retrospective series, the type of KIT exon 11 mutation was correlated with the origin of GIST, but not with prognosis or response to imatinib.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Agents / therapeutic use
  • Benzamides
  • Disease-Free Survival
  • Exons*
  • Female
  • Gastrointestinal Stromal Tumors / drug therapy
  • Gastrointestinal Stromal Tumors / genetics*
  • Gastrointestinal Stromal Tumors / pathology
  • Gastrointestinal Stromal Tumors / surgery
  • Gene Deletion*
  • Humans
  • Imatinib Mesylate
  • Male
  • Middle Aged
  • Piperazines / therapeutic use
  • Proto-Oncogene Proteins c-kit / genetics*
  • Pyrimidines / therapeutic use
  • Retrospective Studies
  • Survival Rate
  • Young Adult


  • Antineoplastic Agents
  • Benzamides
  • Piperazines
  • Pyrimidines
  • Imatinib Mesylate
  • Proto-Oncogene Proteins c-kit