Efficacy of Risk Malignancy Index to differentiate the benign from malignant Ovarian Lesions

Abstract

Objective: To evaluate the diagnostic accuracy of Risk Malignancy Index (RMI) to differentiate Benign from malignant ovarian masses taking histopathology as the gold standard.

Methodology: A total of 89 patients in department of gynecology and obstetrics, Civil Hospital Karachi from with ovarian masses identified on ultrasound findings according to International ovarian tumor analysis group (IOTA), who plan for surgical exploration were included in this study. After surgery, sample was sent for histopathology. RMI was calculated using formula RMI= U x M x CA-125. Based on RMI, lesions were interpreted, as benign and malignant, and Histopathological findings was considered as gold standard for defining the outcome. The data analysis was done by SPSS version 23.

Results: The average age of the patients was 37.21±11.69 years. The histopathological analysis revealed benign lesions in 83.15% and malignant lesions in 16.85% of cases. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy of RMI in differentiating benign from malignant ovarian masses was 86.7%, 97.3%, 86.7%, 97.3% and 95.5% respectively. Additionally, the RMI maintained strong accuracy 96.7% in women under 40, 92.3% in those over 40, and 97.1% in premenopausal women, while the accuracy remained high across parity and BMI groups.

Conclusion: The Malignancy Index concluded to be a better estimate in diagnosing adnexal masses with high risk of malignancy, with an overall diagnostic accuracy of 95.5%, sensitivity of 86.7%, and specificity of 97.3%.