The effectiveness of b-mode ultrasonography, power doppler and elastography in the diagnosis and differentiation between malign and benign in soft tissue tumors

Introduction Soft tissue tumors are common in daily clinical practice. Most of them are benign tumors. One of the main goals during imaging of soft tissues should be to identify malignant tumors. US is preferred as the first imaging method in soft tissue tumors. It is not expensive and is easily accessible. Our aim in this prospective study is to evaluate the benefit of B-mode US, Power Doppler, and Shearwave Elastography in diagonising and distinguishing between benign and malignant soft tissue tumors. Materials and Methods This prospective study was approved by the ethics committee in our institution and written informed consent was obtained from all patients before each examination. B-mode US, Power Doppler and pSWE were perfomed in all cases. The soft tissue tumors' morphological characteristics, vascularization and stiffness were evaluated and recorded. After US examinations trucut biopsy or excisional biopsy was perfomed to obtain histopathological diagnosis. The histopathological diagnosis of the tumors was used as a reference. Cases without histopathological diagnosis were not included in the study. 74 patients with 75 soft tissue tumors were included in the study. Statistics for quantitative variables were expressed as a median (25-75 percentile). The dependence between categorical variables was determined using the chi-square test. Descriptive statistics for categorical variables were given as numbers (percentage). The Mann-Whitney u test was used to compare two independent groups. Values with p<0.05 were considered statistically significant. Results 43 benign and 32 malignant tumors were included in the study. Tumors long axis, shape, tissue compartment occupied, vascularization patterns and pSWE were significant in differentiating between benign and malignant tumors (p <0.05). The median kPa values for benign and malignant soft tissue tumors were 27.8 and 46.5 respectively. The difference was statistically significant (p<0.05). Using the ROC curve, the best cut-off value for the kPa median was determined as 34.9 kPa. The sensitivity and specificity of this value in differentiating benign and malignant tumors were calculated as 65.6% and 70.7 % respectively. Area under curve was 0.664. Tumor margins, tumor's echogenicity, internal composition and homogeneity were not significant in the differention of benign and malignant tumors (p <0.05). Conclusion Our study examined the role of US findings in the differentiation of benign and malignant soft tissue tumors. Tumor size, shape, vascularity, number of compartments occupied by the lesion, and finally the values obtained by SWE were found to be useful in this distinction. In the light of this information, we think that SWE will have a more important role in the differential diagnosis and management of soft tissue tumors with future studies conducted with a larger cohort. Keywords: Ultrasonography, Doppler, Elastography, Shear-wave, Soft tissue tumors