Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Sara Mohsin, M.D. [2] Faizan Sheraz, M.D. [3]
Overview
MRI is preferred over CT , especially for truncal and extremity desmoid tumors . On MRI , desmoid tumor has variable characteristics depending on their cellularity and fibrous content with loss of signal following fat saturation . They appear isointense/hypointense on T1 and hyperintense on T2.
MRI
MRI is required in order to:
Define the relationship of the tumor to adjacent structures
Assess resectability
Find out the need for treatment
Monitor recurrence after surgery MRI is preferred over CT , especially for truncal and extremity tumors MRI may be helpful in the diagnosis of desmoid tumor. Findings on MRI diagnostic of desmoid tumor include:[ 1] [ 2] [ 3] [ 4]
MRI characteristics of desmoid tumors
MRI sequence
Characteristics
T1
T1 C+ (Gd)
Typically enhances avidly
T2/STIR
GE
A 47-year-old woman with desmoid-type fibromatosis in the right axilla with progression (Group 1). This was misdiagnosed as a sarcoma on preoperative CT but as fibromatosis on preoperative MR. The tumor shows iso-signal intensity on coronal T1-weighted image (A) and high signal intensity on axial T2-weighted image (B). The margin is partially ill-defined (white arrows) on axial T2-weighted image (B). A rim of surrounding fat (white arrows) with high signal intensity is clearly seen on T1-weighted image (A). On enhanced T1-weighted axial (C) and coronal (D) images, the tumor shows strong and heterogeneous enhancement with a central area of nonenhancing low signal bands (black arrows). The maximal standardized uptake value on FDG PET was 2.1 (not shown). CT = computed tomography, MR = magnetic resonance, FDG PET = 18F-fluorodeoxy glucose positron emission tomography.Source: Xu H. et al, Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea (HX, HJK, SL, JWL, HNL, MYK); Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China (HX); Department of Thoracic and Cardiovascular Surgery (DKK); and Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea (JSS).
Extra-Abdominal Fibromatosis (Desmoid Tumor): A Rare Tumor of the Lower Extremity Arising from the Popliteal Fossa. Axial image of MRI shows a large, expansive heterogeneous soft tissue mass with contrast, closely applied to the muscular structures, and infiltration and obliteration of adjacent structures (white asteriks).Source: Ali Kaygain M. et al, Department of Cardiovascular Surgery, Erzurum Regional Training and Research Hospital, 25020 Erzurum, Turkey
Reference
↑ Desmoid tumor. Radiopedia(2015) http://radiopaedia.org/articles/aggressive-fibromatosis . Accessed on January 20, 2015
↑ Azizi L, Balu M, Belkacem A, Lewin M, Tubiana JM, Arrivé L (2005). “MRI features of mesenteric desmoid tumors in familial adenomatous polyposis” . AJR Am J Roentgenol . 184 (4): 1128–35. doi :10.2214/ajr.184.4.01841128 . PMID 15788583 . ↑ Vandevenne JE, De Schepper AM, De Beuckeleer L, Van Marck E, Aparisi F, Bloem JL; et al. (1997). “New concepts in understanding evolution of desmoid tumors: MR imaging of 30 lesions” . Eur Radiol . 7 (7): 1013–9. doi :10.1007/s003300050243 . PMID 9265665 . ↑ Lee JC, Thomas JM, Phillips S, Fisher C, Moskovic E (2006). “Aggressive fibromatosis: MRI features with pathologic correlation” . AJR Am J Roentgenol . 186 (1): 247–54. doi :10.2214/AJR.04.1674 . PMID 16357411 .
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