DIAGNOSTIC ACCURACY OF ULTRASONOGRAPHY IN DIAGNOSING TESTICULAR TUMORS USING MRI AS THE GOLD STANDARD

Abstract

Introduction

Testicular tumors require accurate and timely diagnosis to guide appropriate clinical management. Ultrasonography (US) is widely used as the first-line modality due to its accessibility and cost-effectiveness. This study aimed to determine the diagnostic accuracy of US in detecting testicular tumors using MRI as the reference standard.

Methodology

This cross-sectional validation study included 128 male patients aged ≥18 years. Patients presenting with scrotal symptoms between September 2024 and December 2025 were included using consecutive sampling technique. All patients underwent US followed by MRI on a 1.5T scanner at radiology department of Ayub Teaching Hospital- Abbottabad. MRI findings served as the diagnostic standard. validity parameters were calculated from a 2x2 contingency between US findings taking MRI findings as reference standard. Associations between imaging and clinical features and tumor diagnosis were assessed at a 5% significance level.

Results

MRI confirmed a testicular tumor in 87 (67.9%) patients. US correctly identified 73 of these cases. The diagnostic performance of US was: sensitivity 83.91%, specificity 75.61%, PPV 87.95%, NPV 68.89%, and overall diagnostic accuracy 81.25%. Sonographic features significantly associated with tumor diagnosis included hypoechogenicity, irregular margins, and heterogeneous echotexture (p < 0.001). MRI features significantly associated with tumors included hypo-/isointensity on T1-weighted images, hyperintensity on T2-weighted images, restricted diffusion, and contrast enhancement (p < 0.001). Clinical variables such as age, lesion size, and symptom duration were not significantly associated with presence of tumor.

Conclusions

Ultrasonography demonstrates moderate to high sensitivity and diagnostic accuracy. Testicular sonography is an appropriate first-line investigation for suspected testicular tumors. However, MRI is indispensable for lesions with equivocal or suspicious sonographic features, as it improves lesion characterization and reduces misclassification.