Ovarian fibromas/fibrothecomas are uncommon benign tumours of ovary. Due to their solid structure, these benign tumours are sometimes confused with malignant tumours during clinical evaluation.

To determine the clinico‐pathological characteristics of ovarian fibroma/fibrothecoma and analyse the efficiency of risk of malignancy index (RMI) scoring system to distinguish malignancy among these tumours.

Between November 2001 and February 2012, women with a pathological diagnosis of ovarian fibroma/fibrothecoma were identified. Depending on the menopausal status, serum CA‐125 level and ultrasonographic findings, RMI scores were calculated for each of the patients.

During the study period, 43 ovarian fibroma/fibrothecoma (4.7%) were detected among 912 adnexal masses operated. The mean age of the women was 52.2 (range, 21–80 years). Upon calculating RMI scores, 33 women (76.7%) were classified as low risk and 10 women (23.3%) as high risk for malignancy. Sensitivity, specificity, positive predictive value and negative predictive value of the RMI scoring for identification of malignant lesions preoperatively were found as 0%, 76%, 0% and 97%, respectively. Final pathological diagnosis was ovarian fibroma in 13 (30%) women, fibrothecoma in 29 (67%) and fibrosarcoma in one woman (2%).

There are no specific markers for accurate preoperative diagnosis of ovarian fibroma/fibrothecoma. Moreover, according to our results, RMI scoring system does not aid clinicians in this issue either, with a high false‐positive rate and very low sensitivity. Further studies with higher number of cases are needed to state clearly the role of RMI scores in preoperative discrimination of malignancy.