Assessment of soft tissue tumours of the extremities with diffusion echoplanar MR imaging

Abstract

Diffusion-weighted echo-planar MR imaging is a promising noninvasive modality that may be helpful in differentiating malignant soft tissue tumours from benign masses as well as in grading malignancy.

Differentiation of malignant from benign soft tissue tumours: use of additive qualitative and quantitative diffusion-weighted MR imaging to standard MR imaging at 3.0 T

“…It could be related to small patient number and measurement of ADC av in three myxoid malignant tumours including t w o m y x o i d l i p o s a r c o m a s a n d o n e l o w -g r a d e myxofibrosarcoma out of 11 malignant soft tissue tumours in their study [8], as well as use of high b values and combined standard MRI in our study. Razek et al [12] found significant differences in ADCs between malignant and benign soft tissue tumours. Similar to our study, they selected 1.34×10 -3 mm 2 /sec as a cutoff ADC av for differentiating malignant soft tissue tumours from benign masses, which resulted in an accuracy of 91 %, sensitivity of 94 %, specificity of 88 % and an AUC of 0.869 using 1.5 T MRI with b values of 0, 500, and 1000 sec/mm 2 .…”

“…However, the lower diagnostic performance observed in our study might be a result of the different histological types of the lesions included. Unlike the Razek et al study [12], we excluded non-neoplastic lesions and well-differentiated liposarcomas, whereas they included venous malformation [29 % (4/14) of benign lesions] and liposarcoma [26 % (6/23) malignant lesions] without stating the subtype, except for one myxoid liposarcoma. Since ADC is affected by various factors including magnetic field strength, machines, pulse sequences, and selection of b values, the absolute cutoff value between malignancy and benignity is not clear [22].…”

“…On dynamic contrastenhanced MRI, rapid arterial enhancement followed by a plateau or washout phase has been reported to favour malignancy [7]. There have been inconsistent reports [8][9][10][11][12][13][14] using diffusion-weighted imaging (DWI) at 1.5 T for differentiation of malignant from benign soft tissue tumours. Benign lesions such as lipoma, epidermal inclusion cyst, and localized tenosynovial giant cell tumour (giant cell tumour of tendon sheath) can have low apparent diffusion coefficients (ADCs), while malignant tumours with myxoid or chondroid components have high ADCs [10,11,15].…”

Clinical Evaluation and Management of Benign Soft Tissue Tumors of the Extremities

“…Selection of a threshold ADC value for differentiating malignant soft tissue tumors from benign masses resulted in an accuracy of 91 %, sensitivity of 94 %, and a specificity of 88 %. They acknowledged the small number of subjects within their study and recognized the need for larger studies [5]. A study that evaluated the ability of diffusion-weighted MR imaging to differentiate between benign and malignant breast lesions found a linear inverse correlation between ADC and tumor cellularity that allowed the authors to differentiate between these lesions [6].…”

El bileğinde ekstraskeletal mezenkimal kondrosarkomun manyetik rezonans görüntüleme bulguları: olgu sunumu

“…The differential diagnosis of the tumor includes; synovial sarcoma and malignant fibrous histiocytoma which has more recently classified as pleomorphic undifferentiated sarcoma. Synovial sarcomas showed typical intermixed areas of low, intermediate and high signal intensity defining as 'triple sign' on T2 weighted images 8 9 . We found a mean ADC value of 0.98 ± 0.06 x10 -3 mm 2 /sec which is highly suspicious for malignancy.…”