Focal Nodular Hyperplasia on F-18 FDG-PET

Focal nodular hyperplasia (FNH) characteristically has FDG avidity similar to (more common) or lower than the surrounding liver. In rare circumstances, FNH can present as a hypermetabolic lesion, creating some confusion.

The case above shows the typical appearance of focal nodular hyperplasia on CT. FDG-PET shows that the uptake of the lesion (arrow) is similar to the adjacent liver.

Differential considerations on FDG-PET include adenoma, hemangioma, and hepatocellular carcinoma.

References

• Aznar DL, Ojeda R, Garcia EU, Aparici F, Sánchez PA, Flores D, Martínez C, Sopena R. Focal nodular hyperplasia (FNH): a potential cause of false-positive positron emission tomography. Clin Nucl Med. 2005 Sep;30(9):636-7.
• Kurtaran A, Becherer A, Pfeffel F, Müller C, Traub T, Schmaljohann J, Kaserer K, Raderer M, Schima W, Dudczak R, Kletter K, Virgolini I. 18F-fluorodeoxyglucose (FDG)-PET features of focal nodular hyperplasia (FNH) of the liver. Liver. 2000 Dec;20(6):487-90.