Subjective assessment by ultrasound is superior to the risk of malignancy index (RMI) or the risk of ovarian malignancy algorithm (ROMA) in discriminating benign from malignant adnexal masses.

Purpose: The combination of two tumour markers, CA125 and HE4, in the risk of ovarian malignancy assay (ROMA) has been shown to be successful in classifying patients into those who have a high or low risk of epithelial ovarian cancer. In the present study, the diagnostic accuracy of ROMA was assessed and compared to the diagnostic accuracy of the two most widely used ultrasound methods, namely the risk of malignancy index (RMI) and subjective assessment by ultrasound.

Methods: From August, 2005 to March, 2009, 432 women with a pelvic mass who were scheduled to have surgery were enrolled in a single-centre prospective cohort study. A preoperative ultrasound was performed and preoperative CA125 and HE4 serum levels were measured. Once the final surgical pathology reports were obtained, the diagnostic accuracy and performance indices of ROMA, RMI and subjective assessment were calculated.

Results: Of the 432 eligible patients, 374 could be analysed. Subjective assessment had the highest area under the receiver operator characteristic curve (AUC) (0.968, 95%CI:0.945-0.984), followed by the RMI (0.931, 95%CI:0.901-0.955). The subjective assessment and RMI both had significantly higher AUCs than the ROMA (0.893, 95%CI:0.857-0.922; P<0.0001 and P=0.0030, respectively). The pre- and postmenopausal populations generated similar results.

Conclusion: Although new tumour markers models are promising, they do not contribute significantly to the diagnosis of ovarian cancer. Ultrasound, especially subjective assessment by ultrasound, remains superior in discriminating malignant from benign ovarian masses.