Risk of Malignancy Index (RMI) in the Pre-Operative Evaluation of Patients with Adnexal Masses

Abstract

The aim of this study is to evaluate use of RISK of MALIGNANCY INDEX (RMI) in primary evaluation of adnexal masses without clear evidence of malignancy, by combining serum CA 125 levels, USG score and menopausal status. It is a cross sectional study conducted at Department of gynaec- oncology, Gujarat Cancer and Research Institute, Ahmedabad. A total of 40 women aged 20 to 65 years with ultrasound diagnosed adnexal masses, and serum measurement of cancer-associated antigen CA-125 levels, were studied. They all had surgical exploration (laparotomy) between May 2005 to July 2007 .The RMI was based on menopausal status, ultrasound morphology of adnexal masses and absolute level of serum CA-125. RMI cut-off of 200 was chosen. The various testing methods were evaluated for sensitivity, specificity, positive and negative predictive values. The best performance was with a RMI at a cut-off of 200 with a sensitivity of 66.66%, specificity of 63.15%, positive predictive value of 66.66% and negative predictive value of 65.15% to diagnose malignancy. When RMI was used, it is better in detecting benign tumour and malignant tumour rather than individual component. RMI to be a valuable, reliable and applicable method in primary evaluation of patients with adnexal masses, and a usable method for referral of advanced neoplasia to a more complex healthcare unit.