The Prognostic Value of Perioperative Profiles of ACTH and Cortisol for Recurrence after Transsphenoidal Hypophysectomy in Dogs with Corticotroph Adenomas
S.J. van Rijn2 
J.M. Hanson1 
D. Zierikzee2 
H.S. Kooistra2 
L.C. Penning2 
M.A. Tryfonidou2 
[1] Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden;Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
Transsphenoidal hypophysectomy is an effective treatment for dogs with pituitary-dependent hypercortisolism (PDH). However, long-term recurrence of hypercortisolism is a well-recognized problem, indicating the need for reliable prognostic indicators.
Objectives
The aim of this study was to evaluate the prognostic value of perioperative plasma ACTH and cortisol concentrations for identifying recurrence of hypercortisolism after transsphenoidal hypophysectomy.
Animals
A total of 112 dogs with PDH that underwent transsphenoidal hypophysectomy met the inclusion criteria of the study.
Methods
Hormone concentrations were measured preoperatively and 1–5 hours after surgery. Both absolute hormone concentrations and postoperative concentrations normalized to preoperative concentrations were included in analyses. The prognostic value of hormone concentrations was studied with Cox's proportional hazard analysis.
Results
Median follow-up and disease-free period were 1096 days and 896 days, respectively. Twenty-eight percent of patients had recurrence, with a median disease-free period of 588 days. Both absolute and normalized postoperative cortisol concentrations were significantly higher in dogs with recurrence than in dogs without recurrence. High ACTH 5 hours after surgery, high cortisol 1 and 4 hours after surgery, high normalized ACTH 3 hours after surgery, high normalized cortisol 4 hours after surgery and the random slope of cortisol were associated with a shorter disease-free period.
Conclusions and clinical importance
Individual perioperative hormone curves provide valuable information about the risk of recurrence after hypophysectomy. However, because no single cutoff point could be identified, combination with other variables, such as the pituitary height/brain area (P/B) ratio, is still needed to obtain a good estimate of the risk for recurrence of hypercortisolism after hypophysectomy.
Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.