The Diagnostic Value of the Added MR Imaging of the Scrotum in the Preoperative Workup of Sonographically Indeterminate Testicular Lesions—A Retrospective Multicenter Analysis

SIMPLE SUMMARY: This retrospective multi-center study analyzes the diagnostic accuracy of magnetic resonance imaging (MRI) of the scrotum in comparison with standard ultrasound (US) and histopathological specimens. A total of N = 113 patients were included. A total of 53 histopathological specimens were available, with 52.8% malignant and 50.9% benign findings. Related to the histopathology, imaging was true negative, false negative, false positive and true positive in 4.1%, 2.1%, 25.0% and 37.5% for standard ultrasound (US) and 9.1%, 1.8%, 25.5% and 43.6% for MRI. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 94.7%, 20.0%, 36.0% and 88.9% for US and 85.7%, 72.8%, 52.1% and 93.7% for MRI, respectively. Benign lesions were significantly smaller than malignant ones on standard US, MRI and histopathology (all p < 0.05). ABSTRACT: Background: The purpose of this study was to retrospectively analyze the diagnostic accuracy of magnetic resonance imaging (MRI) examinations of the scrotum in comparison with standard ultrasound (US) and histopathology. Methods: A retrospective multi-center analysis of MRI examinations of the scrotum performed between 06/2008 and 04/2021 was conducted. Results: A total of n = 113 patients were included. A total of 53 histopathologies were available, with 52.8% malignant and 50.9% benign findings. Related to histopathology, imaging was true negative, false negative, false positive, and true positive in 4.1%, 2.1%, 25.0% and 37.5% for standard ultrasound (US) and 9.1%, 1.8%, 25.5% and 43.6% for MRI. Sensitivity, specificity, positive predictive value and negative predictive value were 94.7%, 20.0%, 36.0% and 88.9% for US and 85.7%, 72.8%, 52.1% and 93.7% for MRI, respectively. Benign lesions were significantly smaller than malignant ones in standard US (p = 0.001), histopathology (p = 0.001) and MRI (p = 0.004). The size of malignant tumors did not differ significantly between histopathology and standard US (0.72) and between histopathology and MRI (p = 0.88). Conclusions: MRI shows good sensitivity and specificity for the estimation of testicular tumors in this collective. Benign lesions are significantly smaller than malignant ones. Both MRI and US can estimate the size of malignant tumors adequately.