Open AccessValue of Early Post-Operative Growth Hormone Testing in Predicting Long-Term Remission and Residual Disease after Transsphenoidal Surgery for Acromegaly
Author(s) -
Yi Yuen Wang,
Mueez Waqar,
Amr Abdelhamid AbouZeid,
Tara Kearney,
Carmela Caputo,
Julian Davis,
Peter Trainer,
Claire Higham,
Federico Roncaroli,
Kanna Gnanalingham
Publication year - 2021
Publication title -
neuroendocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.493
H-Index - 101
eISSN - 1423-0194
pISSN - 0028-3835
DOI - 10.1159/000517476
Subject(s) - acromegaly , medicine , transsphenoidal surgery , basal (medicine) , gastroenterology , population , endocrinology , univariate analysis , growth hormone , logistic regression , surgery , hormone , adenoma , insulin , pituitary adenoma , multivariate analysis , environmental health
Surgical remission for acromegaly is dependent on a number of factors including tumour size, invasiveness, and surgical expertise. We studied the value of early post-operative growth hormone (GH) level as a predictor of outcome and to guide early surgical re-exploration for residual disease in patients with acromegaly. Methods: Patients with acromegaly undergoing first-time endoscopic transsphenoidal surgery between 2005 and 2015, in 2 regional neurosurgical centres, were studied. Insulin-like growth factor-1 (IGF-1), basal GH (i.e., sample before oral glucose), and GH nadir on oral glucose tolerance test (OGTT) were tested at various time points, including 2–5 days post-operatively. Definition of disease remission was according to the 2010 consensus statement (i.e., GH nadir <0.4 μg/L during an OGTT and normalized population-matched IGF-1). Forward stepwise logistic regression was used to determine factors associated with remission. Results: We investigated 81 consecutive patients with acromegaly, 67 (83%) of which had macroadenomas and 22 (27%) were noted to be invasive at surgery. Mean follow-up was 44 ± 25 months. Overall, surgical remission was achieved in 55 (68%) patients at final follow-up. On univariate analysis, the remission rates at the end of the study period for patients with early post-operative GH nadir on OGTT of <0.4 ( N = 43), between 0.4 and 1 ( N = 28), and >1 μg/L ( N = 8) were 88, 54, and 20%, respectively. Similar results were seen with basal GH on early post-operative OGTT. On multivariate regression analysis, pre-operative IGF-1 (odds ratio of 13.1) and early post-operative basal GH (odds ratio of 5.0) and GH nadir on OGTT (odds ratio of 6.8) were significant predictors of residual disease. Based on a raised early GH nadir and post-operative MR findings, 10 patients underwent early surgical re-exploration. There was reduction in post-operative GH levels in 9 cases, of which 5 (50%) achieved long-term remission. There was an increased risk of new pituitary hormone deficiencies in patients having surgical re-exploration compared to those having a single operation (60 vs. 14%). Conclusions: An early post-operative basal GH and GH nadir on OGTT are reliable predictors of long-term disease remission. It can be used to guide patients for early surgical re-exploration for residual disease, although there is increased risk of hypopituitarism.