Results of adrenalectomy in 36 dogs with hyperadrenocorticism caused by adreno-cortical tumour.

A total of 38 adrenocortical tumours were removed from 36 dogs with hyperadrenocorticism. The surgical approach was by way of a unilateral flank laparotomy (32 dogs; 14 left and 18 right), a bilateral flank laparotomy (3 dogs) or a midline celiotomy (1 dog). Two dogs were euthanized during surgery because their tumours could not be resected. Eight dogs died from post-operative complications. Pancreatic necrosis with peritonitis was the most common cause of death. Eight of the 26 dogs that survived had signs of recurrence of hyperadrenocorticism. Unsuppressible hyperadrenocorticism was found in four dogs; one dog had probably pre-existent pituitary-dependent hyperadrenocorticism, and adrenocortical function could not be re-examined in the remaining three dogs. Among the 37 tumours examined microscopically expansion of neoplastic tissue into blood vessels was found in 22 of them. Four adrenal glands with adrenocortical tumours also contained phaeochromocytomas. Necropsy was performed in eight dogs. Metastases were found in the lungs of two dogs and in the lungs and liver in one dog. In combination with the data of previous reports, it is suggested that histological findings in surgery specimens are not good predictors for the clinical outcome.