Mutant KIT as imatinib-sensitive target in metastatic sinonasal carcinoma

S M Dieter1,2, C Heining1,2,3, A Agaimy4

  • 1Department of Translational Oncology, National Center for Tumor Diseases (NCT) Heidelberg and German Cancer Research Center (DKFZ), Heidelberg, Germany.

Abstract

Insights

This study identified a KIT exon 11 mutation in a rare sinonasal carcinoma, leading to a dramatic response to imatinib therapy. This highlights KIT mutations as actionable targets in diverse cancers.

Area of Science:

  • Oncology
  • Genomics
  • Molecular Biology

Background:

  • Sinonasal carcinomas (SNCs) are rare, histologically diverse tumors with poor prognosis and unknown molecular drivers.
  • Metastatic SNC lacks effective systemic therapies, posing a significant clinical challenge.
  • This study investigated a rare, unclassifiable metastatic SNC refractory to standard treatments.

Observation:

  • Whole-exome and transcriptome sequencing identified a KIT exon 11 mutation (c.1733_1735del, p.D579del) in the patient's tumor.
  • A novel bioinformatics algorithm was developed for analyzing tumor mutational catalogs.
  • Secondary KIT exon 17 mutations (c.2459_2462delATTCinsG, p.D820_S821delinsG) emerged upon progression.

Findings:

  • Molecularly guided imatinib treatment, analogous to gastrointestinal stromal tumor (GIST) therapy, yielded a dramatic and durable response.
  • The patient achieved remission, indicating the KIT exon 11 mutation as a dominant driver.
  • Salvage therapy with regorafenib was effective against the secondary KIT mutations.

Implications:

  • Unbiased genomic profiling can reveal vulnerabilities in rare and unclassifiable cancers.
  • KIT exon 11 mutations are druggable therapeutic targets across various cancer types.
  • Personalized medicine approaches utilizing genomic data can improve outcomes for patients with rare malignancies.