Immunohistochemical expression of c-KIT protein in feline soft tissue fibrosarcomas.
C-KIT is the cellular homolog of the feline sarcoma viral oncogene v-KIT, which encodes the tyrosine kinase receptor protein KIT. Mutations and varied expression of this gene have been demonstrated within multiple neoplasms in people and domestic animals. The purpose of this study was to determine if KIT protein is expressed in feline soft tissue fibrosarcomas (ST FSA) using immunohistochemistry (IHC). The computer database at the Oklahoma Animal Disease Diagnostic Laboratory was searched from January 1, 2006, to December 31, 2007, for any domestic cat with an ST FSA. Routinely stained slides from 46 feline ST FSAs were reviewed and graded based on the scale outlined by Kuntz et al. Immunohistochemistry for KIT protein was performed on one representative section from each cat. There were a total of 12/46 (26%) cats that were immunoreactive for KIT. Immunoreactivity was detected in greater than 80% of the neoplastic cells in 4/46 (9%) cats. Immunoreactivity was detected in less than 10% of the neoplastic cells in 8/46 (17%) cats. Immunoreactivity was characterized by evenly distributed cytoplasmic stippling within the neoplastic spindle-shaped cells and/or multinucleated giant cells. Based on these results, KIT immunoreactivity can be detected within feline ST FSAs using IHC. The results of this study also indicate that KIT immunoreactivity in feline ST FSA does not correlate with the histologic grade (P = .141, X(2) = 2.166), survivability (P = .241, X(2) = 1.373), or whether the neoplasm was a spontaneous or an injection site FSA (P = .074, X(2) = 3.184).
Smith
A J
AJ
Department of Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, USA.
Njaa
B L
BL
Lamm
C G
CG
D000818:Animals; D002371:Cat Diseases / Q000378:metabolism / Q000473:pathology*; D002415:Cats; D005260:Female; D005354:Fibrosarcoma / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D007150:Immunohistochemistry / Q000662:veterinary; D008297:Male; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D016019:Survival Analysis
D019009:Proto-Oncogene Proteins c-kit