The Risk of Malignancy Index in Differentiating Malignant from Benign Ovarian Tumor

Abstract

Background: To solve the issues of preoperative diagnosis of ovarian tumors, risk of malignancy index (RMI) is a suitable index for evaluation of ovarian tumors before surgeries. Objective: In this study our main goal is to evaluate the risk of Malignancy Index in Differentiating Malignant from Benign Ovarian Tumor. Method: This cross sectional study was carried out at Department of Obstetrics and Gynaecology, Shaheed Suhrawardy Medical College Hospital, Dhaka from January 2013 to December where a total of 60 women who diagnosed with ovarian tumor were included as a sample size. Result: During the study, majority of the patients belong to 21-30 years age group, 26.7% and according to histopathology findings (63.3%) cases were benign tumors. Besides that, risk malignancy index (RMI) ≥200 was in 19 (86.4%) cases and RMI <200 was in 32 (53.3%) cases. Of the benign ovarian tumours 34 (89.5%) cases had RMI <200 and 4 (10.5%) cases had RMI ≥200; while of the malignant ovarian tumours 19 (86.4%) cases had RMI ≥200 and 3 (13.6%) cases had RMI<200. In addition, risk malignancy index (RMI) at a cut off value of ≥200 in differentiating malignant from benign ovarian tumours, there were true positive (TP) in 19, false negative (FN) in 3, true negative (TN) in 34 and false positive (FP) in 4. Apart from that, sensitivity of risk malignancy index (RMI) at a cut off value of ≥200 in differentiating malignant from benign ovarian tumours was 86.4% whereas predictive value of risk malignancy index (RMI) at a cut off value of ≥200 in differentiating malignant from benign ovarian tumours was 82.6%. Also, specificity of risk malignancy index (RMI) at a cut off value of ≥200 in differentiating malignant from benign ovarian tumours was 89.5%. Conclusion: RMI can be use as a diagnostic tool to discriminate between malignant and benign ovarian tumours. Hence the RMI is an appropriate method in diagnosing ovarian tumours with high risk of malignancy and guide the gynaecologist for further evaluation and effective management accordingly.