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Imatinib mesylate treatment in a dog with gastrointestinal stromal tumors with a c-kit mutation.

ABSTRACT: A 13-year-old spayed mixed-breed dog was diagnosed with a gastrointestinal stromal tumor (GIST) after histopathological examination of an abdominal mass. Five months after surgical resection of the tumor, we detected the recurrence of GIST with multiple disseminated abdominal lesions. A sequence analysis of cDNA obtained from a biopsy of the recurrent tumors revealed a mutation within exon 9 of the c-kit gene (1523A>T, Asn(508)Ile), which has been shown to cause ligand-independent phosphorylation of the KIT protein in GISTs and canine mast cell tumors (MCTs). Upon detection of the recurrent tumors, we initiated treatment with imatinib mesylate (10 mg/kg, q 24 hr). After 2 months, the dog achieved complete remission. Our findings indicate that canine GIST, and possibly MCT, may be responsive to molecular-targeted therapy.

SUBMITTER: Irie M

PROVIDER: S-EPMC4667679 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Imatinib mesylate treatment in a dog with gastrointestinal stromal tumors with a c-kit mutation.

Irie Mitsuhiro M Takeuchi Yoshinori Y Ohtake Yuzo Y Suzuki Hitomi H Nagata Nao N Miyoshi Takuma T Kagawa Yumiko Y Yamagami Tetsushi T

The Journal of veterinary medical science 20150612 11

A 13-year-old spayed mixed-breed dog was diagnosed with a gastrointestinal stromal tumor (GIST) after histopathological examination of an abdominal mass. Five months after surgical resection of the tumor, we detected the recurrence of GIST with multiple disseminated abdominal lesions. A sequence analysis of cDNA obtained from a biopsy of the recurrent tumors revealed a mutation within exon 9 of the c-kit gene (1523A>T, Asn(508)Ile), which has been shown to cause ligand-independent phosphorylatio ...[more]

PMID: 26074249

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