TY - JOUR
T1 - Hormone secretion by pituitary adenomas is characterized by increased disorderliness and spikiness but more regular pulsing
AU - Roelfsema, Ferdinand
AU - Pereira, Alberto M.
AU - Biermasz, Nienke R.
AU - Veldhuis., Johannes D.
N1 - Publisher Copyright:
Copyright © 2014 by the Endocrine Society.
PY - 2014/10/1
Y1 - 2014/10/1
N2 - Context: Hormone secretion by functioning pituitary tumors is characterized by increased basal (nonpulsatile) secretion, enhanced pulse frequency, amplified pulse mass, and increased disorderliness.Objective: The objective of the study was to quantify (subtle) abnormalities of hormone secretion by pituitary adenomas and the influence of selective pituitary surgery and suppressive medications on these parameters.Results: ApEn and spikiness were markedly increased in all untreated patient groups and normalized after pituitary surgery in acromegaly and hypercortisolism. In contrast, hormone-suppressive medical treatmentin acromegaly and prolactinoma did not normalize ApEn. Spikiness normalized in acromegalic patients but not in prolactinoma. GH and cortisol pulsing regularity was elevated in acromegaly and Cushing's disease, respectively, and normalized after surgery. Medical treatment caused normalization of pulsing regularity in acromegaly but not in prolactinoma patients.Methods: Approximate entropy (ApEn) was quantified with a refined algorithm, spikiness by a new method to evaluate sudden short-lived increases in hormone levels, and pulsing regularity, determined with a fully automated deconvolution program. These 3 distinct measures of secretory disruption were compared in untreated and treated patients with acromegaly, prolactinoma, and Cushing's disease together with matching profiles in healthy controls.Conclusion: This study extends the understanding of disorganized hormone secretion by hyperfunctioning pituitary adenomas. The new findings are increased spikiness in all 3 tumor groups and increased pulsing regularity in GH- and ACTH-secreting adenomas. The mechanisms behind the marked pattern irregularity and the selective normalization by surgical and medical therapies are not established yet but may include diminished feedback signaling in addition to the anatomical and functional disorganization of intrapituitary cell networks.
AB - Context: Hormone secretion by functioning pituitary tumors is characterized by increased basal (nonpulsatile) secretion, enhanced pulse frequency, amplified pulse mass, and increased disorderliness.Objective: The objective of the study was to quantify (subtle) abnormalities of hormone secretion by pituitary adenomas and the influence of selective pituitary surgery and suppressive medications on these parameters.Results: ApEn and spikiness were markedly increased in all untreated patient groups and normalized after pituitary surgery in acromegaly and hypercortisolism. In contrast, hormone-suppressive medical treatmentin acromegaly and prolactinoma did not normalize ApEn. Spikiness normalized in acromegalic patients but not in prolactinoma. GH and cortisol pulsing regularity was elevated in acromegaly and Cushing's disease, respectively, and normalized after surgery. Medical treatment caused normalization of pulsing regularity in acromegaly but not in prolactinoma patients.Methods: Approximate entropy (ApEn) was quantified with a refined algorithm, spikiness by a new method to evaluate sudden short-lived increases in hormone levels, and pulsing regularity, determined with a fully automated deconvolution program. These 3 distinct measures of secretory disruption were compared in untreated and treated patients with acromegaly, prolactinoma, and Cushing's disease together with matching profiles in healthy controls.Conclusion: This study extends the understanding of disorganized hormone secretion by hyperfunctioning pituitary adenomas. The new findings are increased spikiness in all 3 tumor groups and increased pulsing regularity in GH- and ACTH-secreting adenomas. The mechanisms behind the marked pattern irregularity and the selective normalization by surgical and medical therapies are not established yet but may include diminished feedback signaling in addition to the anatomical and functional disorganization of intrapituitary cell networks.
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U2 - 10.1210/jc.2014-2363
DO - 10.1210/jc.2014-2363
M3 - Article
C2 - 25014002
AN - SCOPUS:84907612256
SN - 0021-972X
VL - 99
SP - 3836
EP - 3844
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
IS - 10
ER -