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Ducry J, Gomez F, Prior JO, et al. Mid-gut ACTH-secreting neuroendocrine tumor unmasked with (18)F-dihydroxyphenylalanine-positron emission tomography. Endocrinol Diabetes Metab Case Rep. 2015;2015:140104doi: 10.1530/EDM-14-0104.
Ducry, J., Gomez, F., Prior, J. O., Boubaker, A., Matter, M., Monti, M., Pu, Y., Pitteloud, N., & Portmann, L. (2015). Mid-gut ACTH-secreting neuroendocrine tumor unmasked with (18)F-dihydroxyphenylalanine-positron emission tomography. Endocrinology, diabetes & metabolism case reports, 2015140104. https://doi.org/10.1530/EDM-14-0104
Ducry, Julien, et al. "Mid-gut ACTH-secreting neuroendocrine tumor unmasked with (18)F-dihydroxyphenylalanine-positron emission tomography." Endocrinology, diabetes & metabolism case reports vol. 2015 (2015): 140104. doi: https://doi.org/10.1530/EDM-14-0104
Ducry J, Gomez F, Prior JO, Boubaker A, Matter M, Monti M, Pu Y, Pitteloud N, Portmann L. Mid-gut ACTH-secreting neuroendocrine tumor unmasked with (18)F-dihydroxyphenylalanine-positron emission tomography. Endocrinol Diabetes Metab Case Rep. 2015;2015:140104. doi: 10.1530/EDM-14-0104. Epub 2015 Mar 01. PMID: 25861450; PMCID: PMC4361871.
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Endocrinol Diabetes Metab Case Rep. 2015;2015:140104. doi: 10.1530/EDM-14-0104. Epub 2015 Mar 01.

Mid-gut ACTH-secreting neuroendocrine tumor unmasked with (18)F-dihydroxyphenylalanine-positron emission tomography.

Endocrinology, diabetes & metabolism case reports

Julien Ducry, Fulgencio Gomez, John O Prior, Ariane Boubaker, Maurice Matter, Matteo Monti, Yan Pu, Nelly Pitteloud, Luc Portmann

Affiliations

  1. Services of Endocrinology Diabetes and Metabolism , Lausanne University Hospital , Lausanne , Switzerland.
  2. Nuclear Medicine , Lausanne University Hospital , Lausanne , Switzerland.
  3. Visceral Surgery , Lausanne University Hospital , Lausanne , Switzerland.
  4. Internal Medicine , Lausanne University Hospital , Lausanne , Switzerland.
  5. Institute of Pathology, Lausanne University Hospital , Lausanne, CH-1011 , Switzerland.

PMID: 25861450 PMCID: PMC4361871 DOI: 10.1530/EDM-14-0104

Abstract

UNLABELLED: Ectopic ACTH Cushing's syndrome (EAS) is often caused by neuroendocrine tumors (NETs) of lungs, pancreas, thymus, and other less frequent locations. Localizing the source of ACTH can be challenging. A 64-year-old man presented with rapidly progressing fatigue, muscular weakness, and dyspnea. He was in poor condition and showed facial redness, proximal amyotrophy, and bruises. Laboratory disclosed hypokalemia, metabolic alkalosis, and markedly elevated ACTH and cortisol levels. Pituitary was normal on magnetic resonance imaging (MRI), and bilateral inferior petrosal sinus blood sampling with corticotropin-releasing hormone stimulation showed no significant central-to-periphery gradient of ACTH. Head and neck, thoracic and abdominal computerized tomography (CT), MRI, somatostatin receptor scintigraphy (SSRS), and (18)F-deoxyglucose-positron emission tomography (FDG-PET) failed to identify the primary tumor. (18)F-dihydroxyphenylalanine (F-DOPA)-PET/CT unveiled a 20-mm nodule in the jejunum and a metastatic lymph node. Segmental jejunum resection showed two adjacent NETs, measuring 2.0 and 0.5 cm with a peritoneal metastasis. The largest tumor expressed ACTH in 30% of cells. Following surgery, after a transient adrenal insufficiency, ACTH and cortisol levels returned to normal values and remain normal over a follow-up of 26 months. Small mid-gut NETs are difficult to localize on CT or MRI, and require metabolic imaging. Owing to low mitotic activity, NETs are generally poor candidates for FDG-PET, whereas SSRS shows poor sensitivity in EAS due to intrinsically low tumor concentration of type-2 somatostatin receptors (SST2) or to receptor down regulation by excess cortisol. However, F-DOPA-PET, which is related to amine precursor uptake by NETs, has been reported to have high positive predictive value for occult EAS despite low sensitivity, and constitutes a useful alternative to more conventional methods of tumor localization.

LEARNING POINTS: Uncontrolled high cortisol levels in EAS can be lethal if untreated.Surgical excision is the keystone of NETs treatment, thus tumor localization is crucial.Most cases of EAS are caused by NETs, which are located mainly in the lungs. However, small gut NETs are elusive to conventional imaging and require metabolic imaging for detection.FDG-PET, based on tumor high metabolic rate, may not detect NETs that have low mitotic activity. SSRS may also fail, due to absent or low concentration of SST2, which may be down regulated by excess cortisol.F-DOPA-PET, based on amine-precursor uptake, can be a useful method to localize the occult source of ACTH in EAS when other methods have failed.

References

  1. Eur J Nucl Med Mol Imaging. 2012 Feb;39 Suppl 1:S103-12 - PubMed
  2. Curr Opin Endocrinol Diabetes Obes. 2013 Feb;20(1):27-31 - PubMed
  3. J Clin Endocrinol Metab. 2004 May;89(5):2214-21 - PubMed
  4. Lancet Oncol. 2006 Sep;7(9):728-34 - PubMed
  5. Neuroendocrinology. 2012;95(2):135-56 - PubMed
  6. Am J Physiol Endocrinol Metab. 2005 Aug;289(2):E278-87 - PubMed
  7. J Clin Endocrinol Metab. 2010 Mar;95(3):1207-19 - PubMed
  8. Future Oncol. 2014 Nov;10 (14 ):2259-77 - PubMed
  9. Virchows Arch. 2013 May;462(5):489-99 - PubMed
  10. Acta Endocrinol (Copenh). 1989 Jun;120(6):760-6 - PubMed
  11. N Engl J Med. 2012 Mar 8;366(10):914-24 - PubMed
  12. Radiology. 2001 Aug;220(2):373-80 - PubMed
  13. Eur J Nucl Med Mol Imaging. 2012 Feb;39 Suppl 1:S93-102 - PubMed
  14. Eur J Endocrinol. 2013 Mar 15;168(4):R77-83 - PubMed
  15. J Natl Compr Canc Netw. 2015 Jan;13(1):109-17; quiz 117 - PubMed
  16. Cancer. 2003 Feb 15;97(4):934-59 - PubMed
  17. Endocr J. 2009;56(4):579-84 - PubMed
  18. Endocr Relat Cancer. 2010 Jul 28;17(3):R173-93 - PubMed
  19. World J Gastrointest Endosc. 2010 Oct 16;2(10):325-34 - PubMed
  20. Eur J Nucl Med Mol Imaging. 2009 May;36(5):765-70 - PubMed
  21. Cancer. 2011 Oct 1;117(19):4381-9 - PubMed
  22. J Clin Endocrinol Metab. 2006 Feb;91(2):371-7 - PubMed
  23. Nat Rev Endocrinol. 2014 Feb;10(2):102-14 - PubMed
  24. Gut. 2011 Jul;60(7):1009-21 - PubMed
  25. Eur J Nucl Med Mol Imaging. 2013 Jun;40(6):943-66 - PubMed
  26. Exp Clin Endocrinol Diabetes. 2010 Aug;118(8):524-9 - PubMed
  27. J Clin Endocrinol Metab. 2005 Aug;90(8):4955-62 - PubMed
  28. Klin Wochenschr. 1976 Feb 15;54(4):173-5 - PubMed

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