Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit

Marianne Andersen, Joanna Ganc-Petersen, Jens Otto Lunde Jørgensen, Søren Mellemkjaer, Per H Petersen, Ole Blaabjerg, Claus Hagen

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

BACKGROUND: In vitro, the majority of clinically non-functioning pituitary adenomas (NFPAs) produce gonadotropins or their alpha-subunit; however, in vivo, measurements of alpha-subunit levels may not accurately detect the hypersecretion of the alpha-subunit. AIM: We wanted to estimate the reference intervals and decision limits for gonadotropin alpha-subunit, LH and FSH levels, and aratio (alpha-subunit/LH+FSH), especially taking into consideration patient gender and menstrual status. Furthermore, we wanted to examine if the diagnostic utility of alpha-subunit hypersecretion was improved when the alpha-ratios, rather than simply the alpha-subunit levels, were measured in patients with NFPAs. MATERIAL AND METHODS: Reference intervals for gonadotropin alpha-subunit serum levels and alpha-ratios were established in 231 healthy adults. The estimated cut-off limits were applied to 37 patients with NFPAs. Gonadotropin alpha-subunit, LH and FSH levels were measured and alpha-ratios were calculated. RESULTS: In healthy adults, the cut-offs for alpha-subunit levels were significantly different between men and pre- and postmenopausal women: the cut-offs were 1.10, 0.48 and 3.76 IU/l, respectively. Using these estimated cut-offs, increased alpha-subunit levels were identified in 10 out of 37 (27%) patients with NFPAs. By adding alpha-ratio, in combination with alpha-subunit levels, 23 patients out of 37 (62%) were identified as having elevated alpha-subunit hypersecretion, and 22 out of these 23 patients (96%) had increased alpha-ratios. One premenopausal patient out of 23 had elevated alpha-subunit level but a normal alpha-ratio. CONCLUSION: Our data suggest that adding the simple calculation of alpha-ratio improves the ability of detecting gonadotropin alpha-subunit hypersecretion and thereby indentifying patients with NFPAs.
OriginalsprogEngelsk
TidsskriftClinical and Investigative Medicine
Vol/bind33
Udgave nummer3
Sider (fra-til)E203-12
ISSN0147-958X
StatusUdgivet - 1. jan. 2010

Fingeraftryk

Alpha Subunit Glycoprotein Hormones
Gonadotropins
Serum

Citer dette

Andersen, Marianne ; Ganc-Petersen, Joanna ; Jørgensen, Jens Otto Lunde ; Mellemkjaer, Søren ; Petersen, Per H ; Blaabjerg, Ole ; Hagen, Claus. / Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit. I: Clinical and Investigative Medicine. 2010 ; Bind 33, Nr. 3. s. E203-12.
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title = "Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit",
abstract = "BACKGROUND: In vitro, the majority of clinically non-functioning pituitary adenomas (NFPAs) produce gonadotropins or their alpha-subunit; however, in vivo, measurements of alpha-subunit levels may not accurately detect the hypersecretion of the alpha-subunit. AIM: We wanted to estimate the reference intervals and decision limits for gonadotropin alpha-subunit, LH and FSH levels, and aratio (alpha-subunit/LH+FSH), especially taking into consideration patient gender and menstrual status. Furthermore, we wanted to examine if the diagnostic utility of alpha-subunit hypersecretion was improved when the alpha-ratios, rather than simply the alpha-subunit levels, were measured in patients with NFPAs. MATERIAL AND METHODS: Reference intervals for gonadotropin alpha-subunit serum levels and alpha-ratios were established in 231 healthy adults. The estimated cut-off limits were applied to 37 patients with NFPAs. Gonadotropin alpha-subunit, LH and FSH levels were measured and alpha-ratios were calculated. RESULTS: In healthy adults, the cut-offs for alpha-subunit levels were significantly different between men and pre- and postmenopausal women: the cut-offs were 1.10, 0.48 and 3.76 IU/l, respectively. Using these estimated cut-offs, increased alpha-subunit levels were identified in 10 out of 37 (27{\%}) patients with NFPAs. By adding alpha-ratio, in combination with alpha-subunit levels, 23 patients out of 37 (62{\%}) were identified as having elevated alpha-subunit hypersecretion, and 22 out of these 23 patients (96{\%}) had increased alpha-ratios. One premenopausal patient out of 23 had elevated alpha-subunit level but a normal alpha-ratio. CONCLUSION: Our data suggest that adding the simple calculation of alpha-ratio improves the ability of detecting gonadotropin alpha-subunit hypersecretion and thereby indentifying patients with NFPAs.",
keywords = "Adult, Aged, Female, Follicle Stimulating Hormone, Glycoprotein Hormones, alpha Subunit, Gonadotropins, Humans, Luteinizing Hormone, Male, Middle Aged, Pituitary Neoplasms, Young Adult",
author = "Marianne Andersen and Joanna Ganc-Petersen and J{\o}rgensen, {Jens Otto Lunde} and S{\o}ren Mellemkjaer and Petersen, {Per H} and Ole Blaabjerg and Claus Hagen",
year = "2010",
month = "1",
day = "1",
language = "English",
volume = "33",
pages = "E203--12",
journal = "Clinical and Investigative Medicine",
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Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit. / Andersen, Marianne; Ganc-Petersen, Joanna; Jørgensen, Jens Otto Lunde; Mellemkjaer, Søren; Petersen, Per H; Blaabjerg, Ole; Hagen, Claus.

I: Clinical and Investigative Medicine, Bind 33, Nr. 3, 01.01.2010, s. E203-12.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Hypersecretion of the alpha-subunit in clinically non-functioning pituitary adenomas: Diagnostic accuracy is improved by adding alpha-subunit/gonadotropin ratio to levels of alpha-subunit

AU - Andersen, Marianne

AU - Ganc-Petersen, Joanna

AU - Jørgensen, Jens Otto Lunde

AU - Mellemkjaer, Søren

AU - Petersen, Per H

AU - Blaabjerg, Ole

AU - Hagen, Claus

PY - 2010/1/1

Y1 - 2010/1/1

N2 - BACKGROUND: In vitro, the majority of clinically non-functioning pituitary adenomas (NFPAs) produce gonadotropins or their alpha-subunit; however, in vivo, measurements of alpha-subunit levels may not accurately detect the hypersecretion of the alpha-subunit. AIM: We wanted to estimate the reference intervals and decision limits for gonadotropin alpha-subunit, LH and FSH levels, and aratio (alpha-subunit/LH+FSH), especially taking into consideration patient gender and menstrual status. Furthermore, we wanted to examine if the diagnostic utility of alpha-subunit hypersecretion was improved when the alpha-ratios, rather than simply the alpha-subunit levels, were measured in patients with NFPAs. MATERIAL AND METHODS: Reference intervals for gonadotropin alpha-subunit serum levels and alpha-ratios were established in 231 healthy adults. The estimated cut-off limits were applied to 37 patients with NFPAs. Gonadotropin alpha-subunit, LH and FSH levels were measured and alpha-ratios were calculated. RESULTS: In healthy adults, the cut-offs for alpha-subunit levels were significantly different between men and pre- and postmenopausal women: the cut-offs were 1.10, 0.48 and 3.76 IU/l, respectively. Using these estimated cut-offs, increased alpha-subunit levels were identified in 10 out of 37 (27%) patients with NFPAs. By adding alpha-ratio, in combination with alpha-subunit levels, 23 patients out of 37 (62%) were identified as having elevated alpha-subunit hypersecretion, and 22 out of these 23 patients (96%) had increased alpha-ratios. One premenopausal patient out of 23 had elevated alpha-subunit level but a normal alpha-ratio. CONCLUSION: Our data suggest that adding the simple calculation of alpha-ratio improves the ability of detecting gonadotropin alpha-subunit hypersecretion and thereby indentifying patients with NFPAs.

AB - BACKGROUND: In vitro, the majority of clinically non-functioning pituitary adenomas (NFPAs) produce gonadotropins or their alpha-subunit; however, in vivo, measurements of alpha-subunit levels may not accurately detect the hypersecretion of the alpha-subunit. AIM: We wanted to estimate the reference intervals and decision limits for gonadotropin alpha-subunit, LH and FSH levels, and aratio (alpha-subunit/LH+FSH), especially taking into consideration patient gender and menstrual status. Furthermore, we wanted to examine if the diagnostic utility of alpha-subunit hypersecretion was improved when the alpha-ratios, rather than simply the alpha-subunit levels, were measured in patients with NFPAs. MATERIAL AND METHODS: Reference intervals for gonadotropin alpha-subunit serum levels and alpha-ratios were established in 231 healthy adults. The estimated cut-off limits were applied to 37 patients with NFPAs. Gonadotropin alpha-subunit, LH and FSH levels were measured and alpha-ratios were calculated. RESULTS: In healthy adults, the cut-offs for alpha-subunit levels were significantly different between men and pre- and postmenopausal women: the cut-offs were 1.10, 0.48 and 3.76 IU/l, respectively. Using these estimated cut-offs, increased alpha-subunit levels were identified in 10 out of 37 (27%) patients with NFPAs. By adding alpha-ratio, in combination with alpha-subunit levels, 23 patients out of 37 (62%) were identified as having elevated alpha-subunit hypersecretion, and 22 out of these 23 patients (96%) had increased alpha-ratios. One premenopausal patient out of 23 had elevated alpha-subunit level but a normal alpha-ratio. CONCLUSION: Our data suggest that adding the simple calculation of alpha-ratio improves the ability of detecting gonadotropin alpha-subunit hypersecretion and thereby indentifying patients with NFPAs.

KW - Adult

KW - Aged

KW - Female

KW - Follicle Stimulating Hormone

KW - Glycoprotein Hormones, alpha Subunit

KW - Gonadotropins

KW - Humans

KW - Luteinizing Hormone

KW - Male

KW - Middle Aged

KW - Pituitary Neoplasms

KW - Young Adult

M3 - Journal article

VL - 33

SP - E203-12

JO - Clinical and Investigative Medicine

JF - Clinical and Investigative Medicine

SN - 0147-958X

IS - 3

ER -