Focal uptake of 68Ga-DOTATOC in the pancreas: pathological or physiological correlate in patients with neuroendocrine tumours?

  • Akram Al-Ibraheem
  • Ralph Alexander BundschuhEmail author
  • Johannes Notni
  • Andreas Buck
  • Anna Winter
  • Hans-Jürgen Wester
  • Markus Schwaiger
  • Klemens Scheidhauer
Original Article



Neuroendocrine tumours are frequently located in the upper abdomen and especially in the pancreas. Imaging of the abdomen with somatostatin analogs such as 68Ga-DOTA-Phe1-Tyr3-octreotide (DOTATOC) is a standard approach for imaging neuroendocrine cancer, but is still challenging due to physiological and technical considerations in this area. Therefore, the aim of this study was to further investigate the origin of 68Ga-DOTATOC findings in the pancreas.


Forty-three consecutive patients with neuroendocrine tumours were examined by 68Ga-DOTATOC positron emission tomography (PET)/CT for staging or restaging. As imaging of the upper abdomen is frequently affected by breathing artefacts, PET and CT data were analysed for misalignment and rearranged if necessary. Any noticeable uptake in the pancreas was described. Tracer uptake in the head of the pancreas and the liver was measured by means of maximum and average standard uptake value (SUVmax, SUVav). The reference standards (malignant versus benign) for correlation with PET findings were clinical and radiological follow-up (mean follow-up time 14 months) (n = 37) or histological confirmation (n = 6).


In 23 of 43 studies (54%) misalignment between PET and CT data was found with a mean value of 1.4 cm. Visual assessment demonstrated that 20 of 43 scans (46.6%) showed no uptake in the head of the pancreas. Of 43 scans, 23 (53.4%) showed noticeable uptake with focal pattern in the head of the pancreas in 10 scans and irregular pattern in 13 scans. Follow-up indicated malignant pancreatic lesions in three patients. The pancreatic head to liver SUVav ratios in these patients ranged from 1.62 to 6.85, whereas in cases of uptake without known malignancy ratios ranged from 0.56 to 1.19. Considering SUVmax, the ratio ranged from 3.24 to 9.1 and from 0.84 to 1.47, respectively. No statistically significant difference was noted between uptake in the head of the pancreas and the liver in patients without malignant pancreatic tumours (p > 0.05).


68Ga-DOTATOC uptake in the head of the pancreas is a common finding in patients undergoing 68Ga-DOTATOC PET/CT. However, this finding most likely represents a physiological condition, especially if the uptake in the pancreatic head is similar to the uptake in the liver (uptake ratio head to liver SUVav < 1.4). Therefore, quantification is recommended to avoid false-positive diagnosis. Misalignment due to respiratory motion must always be taken into account.


68Ga-DOTATOC Neuroendocrine tumour Head of pancreas Liver SUV 


Conflicts of interest



  1. 1.
    Boy C, Heusner TA, Poeppel TD, Redmann-Bischof A, Unger N, Jentzen W, et al. (68)Ga-DOTATOC PET/CT and somatostatin receptor (sst1-sst5) expression in normal human tissue: correlation of sst2 mRNA and SUV(max). Eur J Nucl Med Mol Imaging 2011;38:1224–36. doi: 10.1007/s00259-011-1760-x.PubMedCrossRefGoogle Scholar
  2. 2.
    Brandner ED, Wu A, Chen H, Heron D, Kalnicki S, Komanduri K, et al. Abdominal organ motion measured using 4D CT. Int J Radiat Oncol Biol Phys 2006;65(2):554–60.PubMedCrossRefGoogle Scholar
  3. 3.
    Buchmann I, Henze M, Engelbrecht S, Eisenhut M, Runz A, Schäfer M, et al. Comparison of 68Ga-DOTATOC PET and 111In-DTPAOC (Octreoscan) SPECT in patients with neuroendocrine tumours. Eur J Nucl Med Mol Imaging 2007;34(10):1617–26.PubMedCrossRefGoogle Scholar
  4. 4.
    Bundschuh RA, Martinez-Möller A, Ziegler SI, Schwaiger M, Scheidhauer K. Misalignment in PET/CT: relevance for SUV and therapy management. Nuklearmedizin 2008;47(2):N14–5.PubMedGoogle Scholar
  5. 5.
    Gabriel M, Decristoforo C, Kendler D, Dobrozemsky G, Heute D, Uprimny C, et al. 68Ga-DOTA-Tyr3-octreotide PET in neuroendocrine tumors: comparison with somatostatin receptor scintigraphy and CT. J Nucl Med 2007;48:508–18.PubMedCrossRefGoogle Scholar
  6. 6.
    Goerres GW, Kamel E, Seifert B, Burger C, Buck A, Hany TF, et al. Accuracy of image coregistration of pulmonary lesions in patients with non-small cell lung cancer using an integrated PET/CT system. J Nucl Med 2002;43(11):1469–75.PubMedGoogle Scholar
  7. 7.
    Haug A, Auernhammer CJ, Wängler B, Tiling R, Schmidt G, Göke B, et al. Intraindividual comparison of 68Ga-DOTA-TATE and 18F-DOPA PET in patients with well-differentiated metastatic neuroendocrine tumours. Eur J Nucl Med Mol Imaging 2009;36:765–70. doi: 10.1007/s00259-008-1030-8.PubMedCrossRefGoogle Scholar
  8. 8.
    Hermann K, Krause BJ, Bundschuh RA, Dechow T, Schwaiger M. Monitoring response to therapeutic interventions in patients with cancer. Semin Nucl Med 2009;39(3):210–32.CrossRefGoogle Scholar
  9. 9.
    Hofmann M, Maecke H, Börner R, Weckesser E, Schöffski P, Oei L, et al. Biokinetics and imaging with the somatostatin receptor PET radioligand (68)Ga-DOTATOC: preliminary data. Eur J Nucl Med 2001;28:1751–7.PubMedCrossRefGoogle Scholar
  10. 10.
    Koukouraki S, Strauss LG, Georgoulias V, Eisenhut M, Haberkorn U, Dimitrakopoulou-Strauss A. Comparison of the pharmacokinetics of 68Ga-DOTATOC and [18F]FDG in patients with metastatic neuroendocrine tumours scheduled for 90Y-DOTATOC therapy. Eur J Nucl Med Mol Imaging 2006;33(10):1115–22. Epub 2006 Jun 9.PubMedCrossRefGoogle Scholar
  11. 11.
    Kowalski J, Henze M, Schuhmacher J, Maecke HR, Hofmann M, Haberkorn U. Evaluation of positron emission tomography imaging using [68Ga]-DOTA-D-Phe(1)-Tyr(3)-octreotide in comparison to [111In]-DTPAOC SPECT. First results in patients with neuroendocrine tumors. Mol Imaging Biol 2003;5:42–8.PubMedCrossRefGoogle Scholar
  12. 12.
    Kumar U, Sasi R, Suresh S, Patel A, Thangaraju M, Metrakos P, et al. Subtype-selective expression of the five somatostatin receptors (hSSTR1–5) in human pancreatic islet cells: a quantitative double-label immunohistochemical analysis. Diabetes 1999;48(1):77–85.PubMedCrossRefGoogle Scholar
  13. 13.
    Meisetschläger G, Poethko T, Stahl A, Wolf I, Scheidhauer K, Schottelius M, et al. Gluc-Lys([18F]FP)-TOCA PET in patients with SSTR-positive tumors: biodistribution and diagnostic evaluation compared with [111In]DTPA-octreotide. J Nucl Med 2006;47(4):566–73.PubMedGoogle Scholar
  14. 14.
    Modlin IM, Lye KD, Kidd M. A 5-decade analysis of 13,715 carcinoid tumors. Cancer 2003;97(4):934–50.PubMedCrossRefGoogle Scholar
  15. 15.
    Nehmeh SA, Erdi YE, Ling CC, Rosenzweig KE, Schoder H, Larson SM, et al. Effect of respiratory gating on quantifying PET images of lung cancer. J Nucl Med 2002;43(7):876–81.PubMedGoogle Scholar
  16. 16.
    Reubi JC, Waser B, Schaer JC, Laissue JA. Somatostatin receptor sst1-sst5 expression in normal and neoplastic human tissues using receptor autoradiography with subtype-selective ligands. Eur J Nucl Med 2001;28(7):836–46.PubMedCrossRefGoogle Scholar
  17. 17.
    Stahl A, Meisetschläger G, Schottelius M, Bruus-Jensen K, Wolf I, Scheidhauer K, et al. [123I]Mtr-TOCA, a radioiodinated and carbohydrated analogue of octreotide: scintigraphic comparison with [111In]octreotide. Eur J Nucl Med Mol Imaging 2006;33(1):45–52.PubMedCrossRefGoogle Scholar
  18. 18.
    Win Z, Al-Nahhas A, Rubello D, Gross MD. Somatostatin receptor PET imaging with gallium-68 labeled peptides. Q J Nucl Med Mol Imaging 2007;51(3):244–50.PubMedGoogle Scholar

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Akram Al-Ibraheem
    • 1
    • 2
  • Ralph Alexander Bundschuh
    • 1
    Email author
  • Johannes Notni
    • 1
  • Andreas Buck
    • 1
    • 3
  • Anna Winter
    • 1
  • Hans-Jürgen Wester
    • 1
  • Markus Schwaiger
    • 1
  • Klemens Scheidhauer
    • 1
  1. 1.Nuklearmedizinische Klinik und PoliklinikKlinikum rechts der Isar der Technischen Universität MünchenMunichGermany
  2. 2.Department of Radiology and Nuclear MedicineKing Hussein Cancer CenterAmmanJordan
  3. 3.Nuklearmedizinische Klinik und PoliklinikUniversitätsklinikum WürzburgWuerzburgGermany

Personalised recommendations