Lale Umutlu MD, Presenter: Consultant, Bayer AG

Thorsten D. Poeppel, Abstract Co-Author: Nothing to Disclose

Cornelius Deuschl, Abstract Co-Author: Nothing to Disclose

Oliver Mueller, Abstract Co-Author: Nothing to Disclose

Christoph Poettgen, Abstract Co-Author: Nothing to Disclose

Philipp Heusch MD, Abstract Co-Author: Nothing to Disclose

Thomas C. Lauenstein MD, Abstract Co-Author: Nothing to Disclose

Michael Forsting MD, Abstract Co-Author: Nothing to Disclose

Marc U. Schlamann, Abstract Co-Author: Nothing to Disclose

To investigate the diagnostic ability of simultaneous [11C]-Methionin PET/MRI for assessment of tumor delineation and potential differences in tracer uptake values of brain tumors in accordance with the WHO Grading System.

A total of 35 patients with primary or recurrence of brain tumors were enrolled in this trial. Brain tumors were assigned into subgroups according to the WHO Classification and comprised 13 low-grade tumors, 5 grade 3 tumors and 17 high-grade tumors. Simultaneous [11C]-Methionin PET/MRI examinations were performed on a Biograph mMR (3 Tesla, Siemens) applying 0.05mmol kg/bw Gadoteric acid (Dotarem, Guerbet). The scan protocol comprised: 1) FLAIR, 2) DWI, 3) T1 TSE, 4) SWI and 5) MPRAGE post contrast. The datasets were read separately by two radiologists in regard of (1) tumor delineation, (2) overall image quality and (3) artifact impairment utilizing a five-point scale (5= excellent; 1 = non-diagnostic). Maximum standardized uptake values (SUVmax) were measured for all detected tumor lesions. All available data (histology, prior examinations, PET/MRI, follow-up examinations) served as standard of reference. Mean values were compared using Wilcoxon rank sum test.

All PET/MRI examinations were completed successfully and provided high-ratings in overall image quality (4.8) and minor artifact impairment (4.7). Evaluation of SUVmax showed increasing tracer uptake values with increasing malignancy, encompassing mean SUVmax of 2.6 for low-grade tumors, mean SUVmax of 3.2 for grade 3 tumors and mean SUVmax of 4.1 for high grade tumors. Statistical significant increase of SUVmax was detected between low and high grade tumors (p<0.05).

Simultaneous PET/MRI offers high quality assessment of morphologic and metabolic features of brain tumors, providing additional information for prognostic stratification in accordance with WHO grading, while preserving comparable examination times to standardized clinical MR examinations due to simultaneous data acquisition.

Simultaneous PET/MRI bears the potential to offer valuable additional information for differential diagnosis and prognostic stratification of brain tumors.

Umutlu, L, Poeppel, T, Deuschl, C, Mueller, O, Poettgen, C, Heusch, P, Lauenstein, T, Forsting, M, Schlamann, M, Integrated [11C]-Methionin PET/MRI for Diagnosing Brain Tumors in Accordance with WHO Grading.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045729.html