[Tumors of the Thyroid Gland in Dogs--a Local Characteristic in the Area of Leipzig]

Aupperle H., Gliesche K. and Schoon H.A.

Dtsch Tierarztl Wochenschr, 2003. 110(4): p.154-7.

During 17 years (1985-2002) 4.072 necropsies in dogs were performed at the Institut fur Veterinar-Pathologie of the University of Leipzig. 154 of them showed tumors of the thyroid. Retrospective classification of the neoplasia between 1992-2002 revealed 6 adenomas, 18 follicular, 33 solid-follicular and 21 solid carcinomas as well as one squamous cell carcinoma, one medullary (C-cell) carcinoma and one fibrosarcoma. During the time investigated, the number of thyroidal neoplasia out of all tumorous diseases in dogs decreased from 48% in 1986 to 3.8% in 2002. This phenomenon may be the result of an increased use of commercially produced animal food with supplementation of iodine. This may have led to the disappearance of the "typical" disease--thyroidal cancer--in dogs in this endemic area of iodine deficiency. The use of immunohistochemical markers shows that the expression pattern in neoplastic follicular areas mostly corresponds to the intact thyroidea. But in solid tumor regions the expression of thyroglobulin, cytokeratin 19 and neuron specific enolase (NSE) has diminished in most areas. Thyroid transcription factor 1 (TTF-1) is expressed in all carcinomas in variable intensity. Medullary carcinoma typically express calcitonin.