18F-FDG PET/CT and MRI features of myxoid liposarcomas and intramuscular myxomas

• Published in: Skeletal radiology 2018-12, Vol.47 (12), p.1641-1650
• Main Authors: Lunn, Brendan W., Littrell, Laurel A., Wenger, Doris E., Broski, Stephen M.
• Format: Article
• Language: English
• Subjects: Attenuation; Computed tomography; Diagnosis; Fluorine isotopes; Glycolysis; Imaging; Magnetic resonance imaging; Medical imaging; Medicine; Medicine & Public Health; Metabolism; Nuclear Medicine; Orthopedics; Pathology; Patients; Positron emission; Positron emission tomography; Radiology; Scientific Article; Tomography
• ISSN: 0364-2348; 1432-2161
• DOI: 10.1007/s00256-018-3000-y

Objective To examine the imaging characteristics of intramuscular myxomas (IM) and myxoid liposarcomas (MLS) on 18 F-FDG PET/CT and MRI. Materials and methods With IRB approval, our institutional imaging database was searched for pathologically proven IM and MLS evaluated by 18 F-FDG PET/CT and MRI. PET/CT and MRI imaging characteristics were recorded and correlated with pathologic diagnosis. Results We found eight patients (2 M, 6 F) with IM (mean age 65.6 ± 10.4 years) and 16 patients (7 F, 9 M) with MLS (mean age 42.8 ± 16.3 years). MRI was available in 7/8 IM and 15/16 MLS patients. There was no significant difference between the two groups in SUVmax (IM 2.7 ± 0.8, MLS 3.0 ± 1.0; p  = 0.35), SUVmean (1.7 ± 0.4, 1.5 ± 0.5; p  = 0.40), total lesion glycolysis (101.8 ± 127.3, 2420.2 ± 4003.3 cm 3 *g/ml; p  = 0.12), metabolic tumor volume (62.3 ± 71.1, 1742.9 ± 3308.0 cm 3 ; p  = 0.17) or CT attenuation ( p  = 0.70). MLS occurred in younger patients ( p  = 0.0015), were larger (16.4 ± 8.2 vs. 5.6 ± 2.5 cm; p = 0.0015), more often T1 hyperintense ( p  = 0.03), with nodular enhancement ( p  = 0.006), and macroscopic fat on CT ( p  = 0.0013) and MRI ( p  =