Clinical characteristics and outcome in 15 dogs treated with transsphenoidal hypophysectomy for nonfunctional sellar masses

Abstract

Objective: To characterize the clinical features, neurological examination findings, diagnostic imaging results, histopathological findings, and outcome following transsphenoidal hypophysectomy (TSH) in dogs with nonfunctional sellar masses (NFSM).Study design: Multi-institutional retrospective study.Methods: Medical records of dogs that underwent TSH for a NFSM were reviewed for clinical signs, physical and neurological examination findings, diagnostic imaging results, endocrine testing, surgery reports, and outcome. Magnetic resonance (MR) imaging was rereviewed, and tumors were classified using the previously described system according to pituitary tumor extension and vascular involvement. Owners of dogs that survived to discharge were contacted. Results: The majority of dogs presented for mentation change (12/15). The mean pituitary to brain ratio (P/B ratio) was 1.05 (0.6-1.4). Eight dogs had a tumor imaging classification of 5B. Eleven dogs were diagnosed with a nonfunctional pituitary adenoma (NFPA). Perioperative mortality was 33% (5/15). The median survival for all dogs was 232 days (0-1658). When dogs that did not survive to discharge were excluded, the median survival time was 708 days.

Idiopathic and structural episodic nonintentional head tremor in dogs: 100 cases (2004‐2022)

“…Early signs of pituitary mass in humans are headaches and visual impairment, 27 which in dogs are difficult to detect. 28…”

“…This discrepancy between human and canine patients might arise from the fact that, in humans, masses arising from within the sella turcica rarely are permitted to attain any considerable size before the patient undergoes surgery, and therefore dorsal expansion of the mass into the third ventricle rarely is encountered. Early signs of pituitary mass in humans are headaches and visual impairment, 27 which in dogs are difficult to detect 28 . Therefore, in dogs with pituitary mass, mass effect to the third ventricle and CSF circulation has occurred at the time of diagnosis, whereas in humans such mass effect usually is prevented earlier in the clinical course.…”

Transsphenoidal hypophysectomy for the treatment of hypersomatotropism secondary to a pituitary somatotroph adenoma in a dog

“…6,16,17 Transsphenoidal hypophysectomy is also a well-described treatment for pituitarydependent hyperadrenocorticism and nonfunctional pituitary masses in dogs. 5,[18][19][20] Treatment modalities reported for acromegaly resulting from pituitary tumors in dogs are limited to 2 previous case reports, treated with conventional radiation therapy and medical management. 2,4 Following radiation therapy in these dogs, both cases had persistent clinical signs of hypersomatotropism and increased serum IGF-1 concentration, although this subsequently resolved in 1 dog after treatment with pasireotide.…”

“…Recently, transsphenoidal hypophysectomy has been shown to be an effective treatment option for hypersomatotropism‐induced diabetes mellitus in cats with high rates of diabetic remission (71%‐92%) and median survival times of 853‐1347 days reported 6,16,17 . Transsphenoidal hypophysectomy is also a well‐described treatment for pituitary‐dependent hyperadrenocorticism and nonfunctional pituitary masses in dogs 5,18‐20 …”

Cytologic features of canine melanotroph and corticotroph pituitary adenomas

“…While previous studies provided insights into the histologic and immunohistochemical features of canine and feline pituitary adenomas, 8–10 detailed cytologic descriptions have been reported infrequently in the veterinary literature 11,12 . Hypophysectomy is becoming a more available treatment option and also enables a definitive diagnosis via histopathology and immunohistochemistry (IHC) and allows a more rapid preliminary diagnosis via cytologic evaluation 8,13–17 . The aim of this study was to describe the cytologic features of pituitary adenomas in 12 dogs that underwent hypophysectomy.…”