CVJ / VOL 53 / JUNE 2012 623 Case Report Rapport de cas Functioning unilateral adrenocortical carcinoma in a dog Olga Gójska-Zygner, Roman Lechowski, Wojciech Zygner Abstract — An 11-year-old, 24-kg, intact female Siberian husky dog in anestrus had a 2-month history of polyuria and polydipsia. The dog had signs of mineralocorticoid excess such as hypertension and hypokalemia refractory to potassium supplementation. Abdominal ultrasound revealed an irregular mass in the left adrenal gland. The ACTH stimulation test for aldosterone concentration did not reveal hyperaldosteronism. Unilateral adrenalectomy was performed and histopathology identified adrenal cortical carcinoma. All clinical signs of mineralocorticoid excess ceased after surgery. Résumé — Carcinome corticosurrénal unilatéral fonctionnel chez un chien. Une chienne Husky sibérien intacte et âgée de 11 ans, pesant 24 kg, en anœstrus, avait une anamnèse de 2 mois de polyurie et de polydipsie. La chienne présentait des signes d’excédent minéralocorticoïde, comme l’hypertension et l’hypokaliémie, réfractaire à la supplémentation en potassium. Une échographie abdominale a révélé une masse irrégulière dans la glande surrénale gauche. Le test de simulation d’ACTH pour la concentration d’aldostérone n’a pas révélé l’hyperaldostéronisme. Une adrénalectomie unilatérale a été réalisée et l’histopathologie a identifié un corticosurrénalome. Tous les signes cliniques d’excédent minéralocorticoïde ont cessé après la chirurgie. (Traduit par Isabelle Vallières) Can Vet J 2012;53:623–625 A drenocortical tumors are divided into adenomas and car- cinomas. It is estimated that most of them (up to 80%) are malignant adenocarcinomas. These tumors may or may not be endocrinologically active (1,2). In most dogs, the hormone produced and secreted by these tumors is cortisol. Yet, in some cases adrenocortical tumors produce mineralocorticosteroids, mainly aldosterone, or, very rarely, its active precursor deoxycor- ticosterone (3,4). In this report we describe a dog with unilateral adrenocortical carcinoma and recumbency, hypertension, and hypokalemia as the major clinicopathological signs. Case description An 11-year-old, 24-kg, intact female Siberian husky dog in anes- trus was presented to the Centre of Small Animal Health, Clinic Multiwet, with a 2-month history of polyuria, polydipsia, apa- thy, stiffness of the neck and limbs, reluctance to move, weight loss, pseudoanorexia resulting from reluctance to eating because of limb pain or weakness (the dog was fed by the owner in the prone position) and several diagnoses such as diabetes insipidus, renal failure, and liver damage. Diagnoses were based on poly- uria and polydipsia, decrease in urine specific gravity (1.008), increase in urea concentration (20 mmol/L), and increased alanine aminotransferase activity (228 U/L). An electrocardio- gram (ECG) obtained 2 wk earlier by the referring veterinarian did not reveal any abnormalities. The referring veterinarians had administered hydrochlorothiazide, and placed the dog on commercial renal diet and hepatic diet. Eventually, the referring veterinarians were unable to diagnose the disease, considered the prognosis to be unfavorable and, owing to progressive weakness and lack of response to the treatment, recommended euthanasia. On presentation to the Centre of Small Animal Health, Clinic Multiwet, physical examination of the dog revealed recumbency, weakness, limb tremors, tactile and muscular hyperesthesia, normal or mildly increased spinal and cranial reflexes, tachycardia (180 beats/min), tachypnea (60 breaths/ min), and hypertension (systolic arterial pressure 190 mmHg). Temperature was within the reference interval (RI) (38.0°C). The mucous membranes and the skin were normal. The dog was not dehydrated. Initial diagnostic tests included a complete blood (cell) count (CBC), serum biochemical profile, electrolyte analysis, urinalysis, chest and spine X-ray examination, and abdominal ultrasound examination. Results from the CBC, serum bio- chemical profile, and electrolyte analysis revealed thrombocytosis (629 3 10 9 /L; RI: 200 to 580 3 10 9 /L), increased alanine Centre of Small Animal Health, Clinic Multiwet, Warsaw, Poland (Gójska-Zygner); Department of Small Animal Diseases Clinic (Lechowski), and Department of Preclinical Sciences (Zygner), Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland. Address all correspondence to Dr. Olga Gójska-Zygner; e-mail: olgazygner@yahoo.pl Use of this article is limited to a single copy for personal study. Anyone interested in obtaining reprints should contact the CVMA office (hbroughton@cvma-acmv.org) for additional copies or permission to use this material elsewhere.