Avoid common mistakes on your manuscript.
A 6-year-old boy was referred because of a suspected recurrence of a growth hormone (GH)–producing pituitary macro-adenoma, which initially expanded from the sella turcica to the suprasellar and right parasellar region. Over the course of 2.5 years, the patient had undergone three transsphenoidal resections after which biochemical values normalized. At time of referral, the patient again experienced symptoms of localized headache and increasing GH and IGF-1 serum levels. Repeated MRIs were obtained under a dedicated pituitary imaging protocol, but paediatric neuroradiologists were unable to conclusively differentiate between recurring adenoma and post-operative granulation tissue.
As one report of the incidental finding of a macro-adenoma on 18F-fluoroethyl-l-tyrosine ([18F]FET) PET has been described [1], we decided to perform a [18F]FET PET/MRI in our patient, in an attempt to confirm the suspected recurrence. [18F]FET is a non-natural amino acid transported by the amino acid transport system L (LAT), of which particularly the LAT1 isoform is expressed in a variety of tumour cells. A recent study in rat showed higher LAT1 gene levels in GH-producing pituitary tumour cells compared to normal pituitary tissue [2].
In our case, PET/MR-images revealed increased [18F]FET uptake caudomedially of the right internal carotid artery (Fig. 1A/B). The uptake correlated with two nodular lesions of approximately 3 and 5 mm diameter (Fig. 1C), which were indeed progressive in size over time. This confirmed recurrent adenoma foci, and establishes the usability of [18F]FET PET/MRI for imaging of pituitary adenoma. Our patient was referred for radiotherapy, since a fourth resection was not considered possible.
References
Currie GM, Trifunovic M, Kiat H, Saunders C, Chung D, Ong YY, Wilkinson M, Witte K, Magnussen JJ. Pituitary incidentaloma found on O-(2–18F-fluoroethyl)-l-tyrosine PET. Nucl Med Technol. 2014. https://doi.org/10.2967/jnmt.113.136291.
Satou M, Wang J, Nakano-Tateno T, Teramachi M, Suzuki T, Hayashi K, Lamothe S, Hao Y, Kurata H, Sugimoto H, Chik C, Tateno T. L-type amino acid transporter 1, LAT1, in growth hormone-producing pituitary tumor cells. Mol Cell Endocrinol. 2020. https://doi.org/10.1016/j.mce.2020.110868.
Funding
Open access funding provided by University Medical Center Rotterdam (Erasmus MC).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Ethics approval
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent
Informed consent was obtained from all individual participants (in this case, the parents of the patient) included in the study.
Conflict of interest
The authors declare no competing interests.
Additional information
Publisher’s note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
This article is part of the Topical Collection on Endocrinology.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Veldhuijzen van Zanten, S.E.M., Neggers, S.J.C.M.M., Valkema, R. et al. Positive [18F]fluoroethyltyrosine PET/MRI in suspected recurrence of growth hormone–producing pituitary adenoma in a paediatric patient. Eur J Nucl Med Mol Imaging 49, 410–411 (2021). https://doi.org/10.1007/s00259-021-05458-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00259-021-05458-1