Confocal laser scanning analysis of an equine oral mast cell tumor with atypical expression of tyrosine kinase receptor C-KIT.
A 20-year-old female horse showed a nodular, firm, focal ulcerated mast cell tumor at the right dorsobuccal face of the tongue. Histologically, the nonencapsulated tumor consisted of dense, infiltrating aggregates of well-differentiated, Cresyl violet-positive mast cells accompanied by numerous eosinophils. Furthermore, they exhibited a strong, diffuse, intracytoplasmatic immunohistochemical signal for tryptase and a faint membrane-associated and perinuclear signal for tyrosine kinase receptor KIT. Confocal laser scanning microscopy confirmed an aberrant spatial colocalization of KIT in the Golgi apparatus, which may be the result of a defective protein processing within the tumor cells. The tumor was not associated with a poor prognosis.
Seeliger
F
F
Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany. frank.seeliger@altanapharma.com
Hess
O
O
Pröpsting
M J
MJ
Pröbsting
M
M
Naim
H Y
HY
Kleinschmidt
S
S
Woehrmann
T
T
Germann
P G
PG
Baumgärtner
W
W
D000818:Animals; D005260:Female; D006734:Horse Diseases / Q000201:enzymology* / Q000473:pathology* / Q000601:surgery; D006736:Horses; D034801:Mastocytoma / Q000201:enzymology / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D018613:Microscopy, Confocal / Q000662:veterinary; D019009:Proto-Oncogene Proteins c-kit / Q000096:biosynthesis*; D014062:Tongue Neoplasms / Q000201:enzymology* / Q000473:pathology / Q000601:surgery / Q000662:veterinary*
D019009:Proto-Oncogene Proteins c-kit