Value of Multiparametric US in the Assessment of Intratesticular Lesions.

Abstract

Purpose To evaluate the diagnostic accuracy of multiparametric ultrasonography (US) consisting of gray-scale US, color Doppler US, strain elastography, and contrast agent-enhanced US in the assessment of intratesticular lesions. Materials and Methods Institutional review board approval was obtained for this retrospective study. From January 2012 to December 2015, 55 focal testicular lesions that were indeterminate on gray-scale US scans were further characterized with color Doppler US, strain elastography, and contrast-enhanced US. Strain elastography was performed to assess tissue elasticity, and hard lesions were defined as malignant. Color Doppler US and contrast-enhanced US were performed to determine the absence or presence of vascularization. Avascular lesions were defined as benign. Histopathologic results or follow-up examinations served as reference standards. Correct classification rate, sensitivity, specificity, and likelihood ratio were calculated. Results Of 55 testicular lesions, 43 (78.2%) were benign and 12 (21.8%) were malignant. Single-modality sensitivities and specificities were 66.7% and 88.4% for color Doppler US, 100% and 76.7% for contrast-enhanced US, and 100% and 72.1% for strain elastography, respectively. Among 12 malignant lesions, color Doppler US failed to demonstrate vascularization in four (33.3%) lesions, which were positive for cancer at contrast-enhanced US. By combining strain elastography and contrast-enhanced US, a sensitivity of 100% and specificity of 93.0% were achieved in differentiating benign and malignant focal testicular lesions. Positive likelihood ratio was 5.7 for color Doppler US, 4.3 for contrast-enhanced US, 3.6 for strain elastography, 14.3 for strain elastography combined with color Doppler US, and 14.3 for strain elastography combined with contrast-enhanced US. Conclusion Multiparametric US allows for a reliable differentiation of benign and malignant intratesticular lesions and can potentially be useful in deciding whether orchiectomy can be replaced with follow-up or less invasive organ-sparing strategies. © RSNA, 2017.