Abstract
Purpose
This study was done to determine whether interruption of metformin before 18F-FDG PET/CT imaging could prevent the increased 18F-FDG uptake in the intestine caused by this drug.
Methods
Included in the study were 41 patients with known type 2 diabetes mellitus who were referred to our department for evaluation of various neoplastic diseases. Patients underwent two 18F-FDG PET/CT scans, the first while they were on metformin and the second after they had stopped metformin. They stopped metformin and did not take any other oral antidiabetic medication starting 3 days before the second study and their blood glucose level was regulated with insulin when necessary to keep it within the range 5.55–8.33 mmol/l. FDG uptake was graded visually according to a four-point scale and semiquantitatively by recording the maximum standardized uptake value (SUVmax) in different bowel segments. A paired-samples t-test method was used to determine whether there was a significant difference between SUVmax measurements and visual analysis scores of the metabolic activity of the bowel in the PET/CT scans before and after stopping metformin.
Results
Diffuse and intense 18F-FDG uptake was observed in bowel segments of patients, and the activity in the colon was significantly decreased both visually and semiquantitatively in PET/CT scans performed after patients stopped metformin (p<0.05). There was a statistically significant decrease in activity in the small intestine on visual analysis (p<0.05), but semiquantitative measurements did not show a significant decrease in the SUVmax values in the duodenum or jejunum (p>0.05).
Conclusion
Metformin causes an increase in 18F-FDG uptake in the bowel and stopping metformin before PET/CT study significantly decreased this unwanted uptake, especially in the colon, facilitating the interpretation of images obtained from the abdomen and preventing the obliteration of lesions.
Similar content being viewed by others
References
Bischof Delaloye A, Wahl RL. How high a level of FDG abdominal activity is considered normal?. J Nucl Med. 1995;36(suppl):106P. (abstract).
Nakada K, Fisher SJ, Brown RS, Wahl RL. FDG uptake in the gastrointestinal tract: can it be reduced? J Nucl Med 1999;40:22–3.
Stahl A, Weber WA, Avril N, Schwaiger M. Effect of N-butylscopolamine on intestinal uptake of fluorine-18-fluorodeoxyglucose in PET imaging of the abdomen. Nuklearmedizin 2000;39:241–5.
Jadvar H, Schambye RB, Segall GM. Effect of atropine and sincalide on the intestinal uptake of F-18 fluorodeoxyglucose. Clin Nucl Med 1999;24:965–7.
Gontier E, Fourme E, Wartski M, et al. High and typical 18F-FDG bowel uptake in patients treated with metformin. Eur J Nucl Med Mol Imaging 2008;35:95–9.
Miraldi F, Vesselle H, Faulhaber PF, Adler LP, Leisure GP. Elimination of artifactual accumulation of FDG in PET imaging of colorectal cancer. Clin Nucl Med 1998;23:3–7.
Bailey CJ, Mynett KJ, Page T. Importance of the intestine as a site of metformin-stimulated glucose utilization. Br J Pharmacol 1994;112:671–5.
Bailey CJ, Turner RC. Metformin. N Engl J Med 1996;334:574–9.
Ikeda T, Iwata K, Murakami H. Inhibitory effect of metformin on intestinal glucose absorption in the perfused rat intestine. Biochem Pharmacol 2000;59:887–90.
Wilcock C, Bailey CJ. Reconsideration of inhibitory effect of metformin on intestinal glucose absorption. J Pharm Pharmacol 1991;43:120–1.
Wilcock C, Bailey CJ. Sites of metformin-stimulated glucose metabolism. Biochem Pharmacol 1990;39:1831–4.
Wilcock C, Bailey CJ. Accumulation of metformin by tissues of the normal and diabetic mouse. Xenobiotica 1994;24:49–57.
Bailey CJ, Wilcock C, Day C. Effect of metformin on glucose metabolism in the splanchnic bed. Br J Pharmacol 1992;105:1009–13.
Pénicaud L, Hitier Y, Ferré P, Girard J. Hypoglycaemic effect of metformin in genetically obese (fa/fa) rats results from an increased utilization of blood glucose by intestine. Biochem J 1989;262:881–5.
Bailey CJ, Wilcock C, Scarpello JH. Metformin and the intestine. Diabetologia 2008;51:1552–3.
Wang W, Guan KL. AMP-activated protein kinase and cancer. Acta Physiol (Oxf) 2009;196:55–63.
Sanz P. AMP-activated protein kinase: structure and regulation. Curr Protein Pept Sci 2008;9:478–92.
Santomauro Júnior AC, Ugolini MR, Santomauro AT, Souto RP. Metformin and AMPK: an old drug and a new enzyme in the context of metabolic syndrome. Arq Bras Endocrinol Metabol 2008;52:120–5.
Roy FN, Beaulieu S, Boucher L, Bourdeau I, Cohade C. Impact of intravenous insulin on 18F-FDG PET in diabetic cancer patients. J Nucl Med 2009;50:178–83.
Yasuda S, Takahashi W, Takagi S, Fujii H, Ide M, Shohtsu A. Factors influencing physiological FDG uptake in the intestine. Tokai J Exp Clin Med 1998;23:241–4.
Acknowledgments
We express special thanks to Mrs. Funda Sezgin for her help with the statistical analysis.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Özülker, T., Özülker, F., Mert, M. et al. Clearance of the high intestinal 18F-FDG uptake associated with metformin after stopping the drug. Eur J Nucl Med Mol Imaging 37, 1011–1017 (2010). https://doi.org/10.1007/s00259-009-1330-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00259-009-1330-7