ClinicalTrials.gg
RecruitingNCT06584123FET-pit-PETUpdated Jan 6, 2026

Molecular Pituitary Imaging Using 18F-FET PET

An interventional study of 18F-Fluoro-ethyl-tyrosine (FET) PET in Pituitary Adenoma, sponsored by University of Cambridge. Recruiting at 1 site in United Kingdom. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-01-06.

Sponsored by University of Cambridge · Not applicable, Interventional, and Diagnostic

From the registry’s dates

  • Started Sep 2024; still recruiting 2 years 2 months later.
Phase
Not applicable
Study type
Interventional
Enrollment
20
Allocation
Not applicable
Ages
18 Years to 100 Years
Sex
All
01

Study summary

The goal of this single centre pilot study is to explore whether 18F-fluoro-ethyl-tyrosine PET (FET-PET) yields comparable findings to 11C-methionine PET (Met-PET) for the localisation of pituitary tumours.

Read the detailed description

Up to 20 patients with pituitary adenomas (PA) who have previously undergone 11C-methionine PET (Met-PET) as part of routine clinical care will undergo 18F-fluoroethyltyrosine PET (FET-PET). Patients with newly diagnosed PA or residual/recurrent pituitary tumours following previous treatment will be eligible for recruitment to the study.

Quantitative and qualitative analyses will be performed to assess whether MET-PET and FET-PET yield comparable findings in patients with newly diagnosed or recurrent PA.

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Conditions studied

  • Pituitary Adenoma

Browse trials for

Keywords

  • Molecular pituitary imaging
  • Functional pituitary imaging
  • 18F-FET PET
03

In context

Pituitary Neoplasms

200 studies on the registry are indexed under Pituitary Neoplasms; 51 are open to participants now.

This study's planned enrollment of 20 is below the median of 60 across 121 interventional studies indexed under Pituitary Neoplasms.

Browse Pituitary Neoplasms studies →

Lead sponsor

University of Cambridge is the lead sponsor of 116 studies on the registry; 23 are open to participants now.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
18 Years to 100 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Participant is willing and able to give for participation in the study
  • Male or female, age 18 or above
  • Presence of pituitary adenoma suspected on the basis of clinical/biochemical and/or radiological findings
  • Previous 11C-Met-PET/CT

Exclusion criteria

Exclusion criteria

  • Inability to give
  • Pregnancy or suspected pregnancy
  • Inability to lie supine for 30-60 minutes
  • Patient body habitus above scanner dimensions
  • Known allergy to intravenous radiographic contrast agents
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Phase
Not applicable
Primary purpose
Diagnostic
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
20 participants (estimated)

Study arms

  • Experimental
    Study cohort

    All patient's enrolled in the study will undergo an 18F-FET-PET

    Diagnostic Test: 18F-Fluoro-ethyl-tyrosine (FET) PET

Interventions

  • Diagnostic test18F-Fluoro-ethyl-tyrosine (FET) PET

    18F-Fluoro-ethyl-tyrosine PET study of the pituitary

06

What researchers measure

Primary outcomes

  1. Maximum Standardized Uptake Values (SUVmax) over pituitary tumour on each of 11C-methionine and 18F-fluoroethyltyrosine PET scans

    Comparison of maximum Standardized Uptake Values (SUVmax) measured over pituitary tumours on each type of PET scan.

    Time frame: 1 day

Secondary outcomes

  1. Maximum Standardized Uptake Values (SUVmax) over normal pituitary gland and parasellar structures (e.g. cavernous sinuses) on each of 11C-methionine and 18F-fluoroethyltyrosine PET scans

    Comparison of maximum Standardized Uptake Values (SUVmax) measured over normal pituitary gland and parasellar structures (e.g. cavernous sinuses) on each type of PET scan.

    Time frame: 1 day

07

Study locations

1 of 1 sites recruiting
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References and documents

Publications

  • MacFarlane J, Bashari WA, Senanayake R, Gillett D, van der Meulen M, Powlson AS, Kolias A, Koulouri O, Gurnell M. Advances in the Imaging of Pituitary Tumors. Endocrinol Metab Clin North Am. 2020 Sep;49(3):357-373. doi: 10.1016/j.ecl.2020.06.002. Epub 2020 Jul 15. PubMed 32741476 ↗
  • Koulouri O, Kandasamy N, Hoole AC, Gillett D, Heard S, Powlson AS, O'Donovan DG, Annamalai AK, Simpson HL, Akker SA, Aylwin SJ, Brooke A, Buch H, Levy MJ, Martin N, Morris D, Parkinson C, Tysome JR, Santarius T, Donnelly N, Buscombe J, Boros I, Smith R, Aigbirhio F, Antoun NM, Burnet NG, Cheow H, Mannion RJ, Pickard JD, Gurnell M. Successful treatment of residual pituitary adenoma in persistent acromegaly following localisation by 11C-methionine PET co-registered with MRI. Eur J Endocrinol. 2016 Nov;175(5):485-498. doi: 10.1530/EJE-16-0639. Epub 2016 Aug 25. PubMed 27562400 ↗
  • Koulouri O, Steuwe A, Gillett D, Hoole AC, Powlson AS, Donnelly NA, Burnet NG, Antoun NM, Cheow H, Mannion RJ, Pickard JD, Gurnell M. A role for 11C-methionine PET imaging in ACTH-dependent Cushing's syndrome. Eur J Endocrinol. 2015 Oct;173(4):M107-20. doi: 10.1530/EJE-15-0616. Epub 2015 Aug 5. PubMed 26245763 ↗
  • Koulouri O, Hoole AC, English P, Allinson K, Antoun N, Cheow H, Burnet NG, Donnelly N, Mannion RJ, Gurnell M. Localisation of an occult thyrotropinoma with 11C-methionine PET-CT before and after somatostatin analogue therapy. Lancet Diabetes Endocrinol. 2016 Dec;4(12):1050. doi: 10.1016/S2213-8587(16)30311-4. Epub 2016 Oct 21. No abstract available. PubMed 27777050 ↗
  • Bashari WA, Senanayake R, Koulouri O, Gillett D, MacFarlane J, Powlson AS, Fernandez-Pombo A, Bano G, Martin AJ, Scoffings D, Cheow H, Mendichovszky I, Tysome J, Donnelly N, Santarius T, Kolias A, Mannion R, Gurnell M. PET-guided repeat transsphenoidal surgery for previously deemed unresectable lateral disease in acromegaly. Neurosurg Focus. 2020 Jun;48(6):E8. doi: 10.3171/2020.3.FOCUS2052. PubMed 32480379 ↗
  • Grosu AL, Astner ST, Riedel E, Nieder C, Wiedenmann N, Heinemann F, Schwaiger M, Molls M, Wester HJ, Weber WA. An interindividual comparison of O-(2-[18F]fluoroethyl)-L-tyrosine (FET)- and L-[methyl-11C]methionine (MET)-PET in patients with brain gliomas and metastases. Int J Radiat Oncol Biol Phys. 2011 Nov 15;81(4):1049-58. doi: 10.1016/j.ijrobp.2010.07.002. Epub 2011 May 11. PubMed 21570201 ↗
  • Currie GM, Trifunovic M, Kiat H, Saunders C, Chung D, Ong YY, Wilkinson M, Witte K, Magnussen J. Pituitary incidentaloma found on O-(2-18F-fluoroethyl)-l-tyrosine PET. J Nucl Med Technol. 2014 Sep;42(3):218-22. doi: 10.2967/jnmt.113.136291. Epub 2014 Jun 19. PubMed 24948822 ↗
  • van den Bergh AC, Pruim J, Links TP, van der Vliet AM, Sluiter W, Wolffenbuttel BH, Langendijk JA, Hoving EW, Dullaart RP. Tyrosine positron emission tomography and protein synthesis rate in pituitary adenoma: different effects of surgery and radiation therapy. Radiother Oncol. 2011 Feb;98(2):213-6. doi: 10.1016/j.radonc.2010.12.020. Epub 2011 Feb 4. PubMed 21296442 ↗

Individual participant data

Plan to share: No

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jan 6, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT06584123
Responsible party
Professor Mark Gurnell (Professor of Clinical Endocrinology, University of Cambridge) — Principal investigator
First posted
Sep 4, 2024
Start date
Sep 3, 2024
Primary completion
Sep 2, 2026 (estimated)
Completion
Dec 31, 2026 (estimated)
Last update
Jan 6, 2026

Study contacts

James MacFarlane
Contact
jm2267@medschl.cam.ac.uk
01223 250882
Mark Gurnell, MD, PhD
principal investigator · Cambridge University Hospitals NHS Foundation Trust

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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