THE OCCURRENCE OF CORTICOTROPHINOMA IN CROSS-BREED AND BREED DOGS

The aim of this study was to evaluate the presentation of corticotrophinoma in regard to its size and ACTH production in cross-breed and pure breed dogs. A retrospective study based on clinical histories from 2003-2008 was carried out on dogs with confirmed Pituitary Dependent Hypercortisolism (PDH) (n=100). Evaluation of the pituitary was performed by nuclear magnetic resonance imaging (NMRI) and tumours were classified according to their projection with respect to the sella turcica as intrasellar (IS) or extrasellar (ES). 26% (26/100) of the evaluated patients were cross-breeds and 74% (74/100) were dogs of different pure breeds. Both ACTH plasma concentration and urinary cortisol/creatinine ratio did not show significant differences between pure breed and cross-breed dogs. With regard to the frequency of presentation of 13 and ES adenomas, no significant differences were observed neither between cross-breed and pure breed dogs nor between the different breeds studied. Thus, it can be concluded that there is no breed predilection for the presentation of IS or ES adenomas in dogs with PDH.