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

Abstract

Background A wide range of specificity values for the differentiation of benign and malignant soft‐tissue tumors show the limitations of conventional MRI features. The data obtained by quantitative analysis of diffusion‐weighted image (DWI) and dynamic contrast‐enhanced (DCE) MRIs would provide more objective results, especially in terms of cellularity and perfusion. Purpose To evaluate the diagnostic efficacies of DWI and DCE MRI for the differentiation of malignant and benign soft‐tissue tumors. Study Type Retrospective. Subjects In all, 136 patients (68 females, 68 males; age range 18–86 years, mean age 57.2 years) with soft‐tissue tumors. Field Strength/Sequence 3 T, DWI, DCE. Assessment Tumor sizes, margins, locations, the presence of involvement in bone or neurovascular bundle, peritumoral edema, heterogeneity, and tumor necrosis were investigated on conventional MR images. On DWIs, visual signal drops were assessed and ADC (apparent diffusion coefficient) values were measured. Ktrans, Kep, Ve, and iAUC values, and time–concentration curve (TCC) types were determined using DCE images. Statistical Tests The data were statistically analyzed to determine the abilities to differentiate benign and malignant tumors using the chi‐square test, two‐sample t‐test, and receiver operating characteristic (ROC) analysis. Results Seventy‐three cases were malignant and 63 benign. Age (mean ages of benign/malignant tumors, 51.75/61.86 years; P = 0.0002) and gender (F:M = 40:23 [benign], F:M = 28:45 [malignant], P = 0.003) influenced the distinction between benign and malignant. Sizes, margins, neurovascular bundle involvement, peritumoral edema, and heterogeneity of the tumors on conventional MR images and DCE parameters (Ktrans, Kep, Ve, and iAUC, and TCC plots) obtained from focal region of interest within a narrow volume of interest significantly differentiated benign and malignant lesions (all P < 0.0001, except Ve [P = 0.0004]). For DWI with ADC mapping, all ADC values and visually signal drops were also significant (P < 0.0001). Data Conclusion DWI and DCE‐MRI and derived variables were significantly helpful in discriminating benign and malignant soft‐tissue tumors complementary to conventional MRI. Level of Evidence: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:798–809.

A Pilot Evaluation of Magnetic Resonance Imaging Characteristics Seen With Primary Soft Tissue Giant Cell Tumor in 2 patients

“…DWI is a new method used to differentiate benign from malignant soft tissue lesions based on ADC values; quantitative DWI is useful for differentiating between malignant and benign superficial masses [12][13][14] . Typically, if the ADC value is higher than the threshold of 1.0×10 -3 mm 2 /s, the lesion of superficial soft-tissue mass is considered to be benign [12] .…”

“…In this study, the 500s/mm 2 of b value was performed and the mean ADC value of solid GCT-ST lesions was 2.19×10 −3 mm 2 /s, which was higher compared to the surrounding healthy tissue and the threshold. Some authors have reported considerable overlap between the ADC values in benign and malignant tumors, which is thought to be due to the heterogeneous nature of soft-tissue tumors, including intratumoral water content that increases diffusion, and mucinous contents and intratumoral necrosis [12,13] . We speculate that high ADC values of solid GCT-ST are more useful in representing tumor histology for intensely enhancing solid masses with no detectable macroscopic necrotic or myxoid predominant areas, although tumors interstitial hemorrhage were detected in the current study.…”

“…Most of the existing reports are pathological and clinical studies, while the imaging aspects have only been reported in the cases of adjacent bone or with atypical cystic degeneration [2][3][4][5][6][7][8][9][10][11] . With regard to MR or ultrasonography imaging features, superficial masses can be further identified based on facial edema, skin thickening, skin contact, internal hemorrhage or necrosis and lobulation of the mass [12][13][14][15] . Unlike deep-seated masses, size criteria, i.e., 50mm in diameter, is not an important factor in patients with superficial soft-tissue lesions.…”

A Pilot Evaluation of Magnetic Resonance Imaging Characteristics Seen With Primary Soft Tissue Giant Cell Tumor in 2 patients

“…DWI is new method used to differentiate benign from malignant soft tissue lesions based on ADC values; quantitative DWI are useful for differentiating between malignant and benign superficial masses [12][13][14] . In this study, 500s/mm 2 of b value was performed and mean ADC value of solid GCT-ST lesions was 2.19×10 −3 mm 2 /s, which was higher compared to the surrounding normal soft tissue.…”

“…tumors, which is thought to be due to the heterogeneous nature of soft-tissue tumors, including intratumoral water content that increases diffusion, and mucinous contents and intratumoral necrosis [12,13] . We speculate that high ADC value of solid GCT-ST are more useful in representing tumor histology for intensely enhancing solid masses with no detectable macroscopic necrotic or myxoid predominant areas, although tumors interstitial hemorrhage were detected in the current study.…”