MRI Accuracy in Diagnosing Sonographically Indeterminate Masses Taking Histopathology as Standard

Abstract

Introduction: Approximately 25% of ultrasound-detected adnexal masses pose clinical challenges, being indeterminately categorized as benign or malignant. Characterizing them is pivotal for deciding surgery or pelvic MRI.

Aims and Objectives: To validate the accuracy of MRI for diagnosing sonographically indeterminate masses using biopsy as the gold standard.

Place and Duration of study: A validation cross-sectional study was performed at the Department of Radiology, Mayo Hospital, Lahore, for a period of six months i.e. from December 2019 to June 2020.

Material and Methods: Non-probability consecutive sampling was employed to select 289 patients (12-60 years) with sonographically indeterminate adnexal masses. All those patients who were unwilling to participate or had MRI contraindications like metallic inserts, pacemakers, and claustrophobia were excluded from the study. Data was collected using the proforma as approved by IRB. All patients underwent MR imaging on a 1.5-T GE unit, and MRI accuracy was calculated. The analysis of data was performed using SPSS 25.0 version software, p-value ? 0.05 was taken as significant.

Results: MRI sensitivity, specificity, PPV, NPV, FP, FN, and diagnostic accuracy in sonographically inconclusive adnexal lesions were 94.25%, 85.22%, 90.61%, 90.74%, 3.46%, 5.88% and 90.66%, respectively, referencing histopathology.

Conclusion: The study concludes MRI as a noninvasive, accurate modality for distinguishing benign and malignant adnexal masses. While IOTA Simple Rules can't categorize all masses, around 20% with inconclusive results may need alternative evaluation, like skilled ultrasound examination& MRI. It significantly enhances preoperative differentiation, aiding surgeons in making informed decisions regarding treatment approaches.