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

Abstract

Objectives To determine the added value of diffusionweighted imaging (DWI) to standard magnetic resonance imaging (MRI) to differentiate malignant from benign soft tissue tumours at 3.0 T. Methods 3.0 T MR images including DWI in 63 patients who underwent surgery for soft tissue tumours were retrospectively analyzed. Two readers independently interpreted MRI for the presence of malignancy in two steps: standard MRI alone, standard MRI and DWI with qualitative and quantitative analysis combined. Results There were 34 malignant and 29 non-malignant soft tissue tumours. In qualitative analysis, hyperintensity relative to skeletal muscle was more frequent in malignant than benign tumours on DWI (P=0.003). In quantitative analysis, ADCs of malignant tumours were significantly lower than those of nonmalignant tumours (P≤0.002): 759±385 vs. 1188±423 μm 2 / sec minimum ADC value, 941±440 vs. 1310±440 μm 2 /sec average ADC value. The mean sensitivity, specificity and accuracy of both readers were 96 %, 72 %, and 85 % on standard MRI alone and 97 %, 90 %, and 94 % on standard MRI with DWI.Conclusions The addition of DWI to standard MRI improves the diagnostic accuracy for differentiation of malignant from benign soft tissue tumours at 3.0 T. Key Points • DWI has added value for differentiating malignant from benign soft tissue tumours. • Addition of DWI to standard MRI at 3.0 T improves the diagnostic accuracy. • Measurements of both ADC min within solid portion and ADC av are helpful.

Giant cell tumor of soft tissue: a case report with emphasis on MR imaging

“…Nagata et al [12] reported that three of five giant cell tumors of the tendon sheath (tenosynovial giant cell tumor) showed low ADCs, mimicking malignant soft tissue tumors. Since our case revealed hypointense to intermediate signal on T2-weighted images and low ADCs on DWI despite the benign appearances, giant cell tumor was the favorable diagnosis [13]. However, the mass was not a bone lesion, so tenosynovial giant cell tumor (giant cell tumor of the tendon sheath) was included in our differential diagnosis, even though the lesion was not located adjacent to a tendon in our patient.…”

“…However, the mass was not a bone lesion, so tenosynovial giant cell tumor (giant cell tumor of the tendon sheath) was included in our differential diagnosis, even though the lesion was not located adjacent to a tendon in our patient. On DWI a giantcell-containing benign soft tissue tumor sometimes shows impeded diffusivity (water movement) mimicking malignancy [12,13], and knowing these DWI features in addition to the standard MR findings could help suggest a benign soft tissue lesion. Hemangioma and myositis ossificans were included in the differential diagnosis because of mineralization.…”

Diagnostic performance of diffusion‐weighted (DWI) and dynamic contrast‐enhanced (DCE) MRI for the differentiation of benign from malignant soft‐tissue tumors

“…Furthermore, the selection of b‐value can have marked effects on measured ADC values. When low b‐values are used, ADC can be compromised by perfusion effects, as perfusion may artificially increase the ADC values of malignant lesions . However, the optimal number and scale of b value selection are controversial .…”

“…Until now, there have been several studies to evaluate the clinical usefulness of DWI and DCE‐MRI, respectively, to differentiate between benign and malignant soft‐tissue tumors. However, there are few studies for the differential diagnosis of soft‐tissue tumors by considering both DWI and DCE‐MRI.…”

Single-Shot Echo-Planar Diffusion-Weighted MR Imaging at 3T and 1.5T for Differentiation of Benign Vertebral Fracture Edema and Tumor Infiltration

“…We are unable to describe the exact etiology of this phenomenon. Nevertheless, ADC value is certainly affected by b value, as well as magnetic field strength (18). We investigated whether the addition of DWI (b value of 400 or 1000) to the routine MR image influenced the sensitivity, specificity, or accuracy of the diagnostic differentiation between benign and malignant lesions.…”