Mitotane (o,p'-DDD) resistance in a dog with pituitary-dependent hyperadrenocorticism and phaeochromocytoma.
A dog was presented with a 2 year history of polyuria and polydipsia due to pituitary-dependent hyperadrenocorticism. A low-dose dexamethasone suppression test and measurement of plasma ACTH concentration confirmed the diagnosis. Treatment was instituted with mitotane at 44 mg/kg/day and then 88 mg/kg/d without complete resolution of signs. The dog collapsed with signs consistent with liver disease and was euthanased. Necropsy revealed a phaeochromocytoma of the left adrenal medulla with extensive metastases to the liver. A chromophobe adenoma of the pars intermedia of the pituitary was found.
Bennett
P F
PF
Companion Animal Referral Service, Mt Waverly, Victoria.
Norman
E J
EJ
D000304:Adrenal Cortex Function Tests / Q000662:veterinary; D000310:Adrenal Gland Neoplasms / Q000150:complications / Q000188:drug therapy / Q000662:veterinary*; D000313:Adrenal Medulla / Q000473:pathology; D000308:Adrenocortical Hyperfunction / Q000188:drug therapy / Q000209:etiology / Q000662:veterinary*; D000818:Animals; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D004283:Dog Diseases / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D004285:Dogs; D019008:Drug Resistance, Neoplasm; D005065:Euthanasia / Q000662:veterinary; D005260:Female; D008113:Liver Neoplasms / Q000556:secondary / Q000662:veterinary; D008939:Mitotane / Q000627:therapeutic use*; D010673:Pheochromocytoma / Q000150:complications / Q000188:drug therapy / Q000556:secondary / Q000662:veterinary*; D010900:Pituitary Diseases / Q000150:complications / Q000188:drug therapy / Q000662:veterinary
D018931:Antineoplastic Agents, Hormonal; D008939:Mitotane