Benign giant cell tumour of tendon sheaths in a European Lynx (Lynx lynx).
The histological, histochemical, immunohistochemical and ultrastructural features of a benign giant cell tumour (BGCT) of tendon sheaths in a 12-year-old male European lynx (Lynx lynx) are reported herein. The neoplastic mass involved the subcutaneous and inter-muscular tissues of the first, second, third and fourth digit of the left forelimb, from the phalanxes up to the carpus. The tumour appeared as a grey-whitish tissue mottled with darker areas, along with several scattered foci of orange colour. Histologically, the lesion consisted of a mixed population of numerous, multinucleated giant cells and epithelioid or spindle-shaped mononuclear cells embedded in a loose, highly vascular stroma. Neoplastic cells lined cleft formations and synovial-like projections into cystic spaces. No osteoid matrix could be detected. Haemorrhage and necrosis were also observed. The mononuclear and the giant cells were tartrate-resistant acid phosphatase and periodic acid-Schiff positive, being also immunohistochemically reactive for lysozyme and vimentin, with a few cells showing immunopositivity also for alpha-1-antitrypsin. Ultrastructurally, histiocyte-like cells, fibroblast-like cells and multinucleated giant cells were observed, but no virus-like particles could be detected in any of the above cell types. The BGCT of tendon sheaths, a fairly uncommon neoplasm in animals, has not been previously reported in the lynx.
Malatesta
D
D
Department of Comparative Biomedical Sciences, Faculty of Veterinary Medicine, University of Teramo, Italy.
Cuomo
A
A
Marà
M
M
Di Guardo
G
G
Gentile
L
L
Macolino
A
A
Della Salda
L
L
D000818:Animals; D005870:Giant Cell Tumors / Q000473:pathology / Q000601:surgery / Q000648:ultrastructure / Q000662:veterinary*; D007150:Immunohistochemistry / Q000662:veterinary; D046008:Lynx; D008297:Male; D013710:Tendons / Q000473:pathology*