Evaluation of adnexal tumours in the International Ovarian Tumor Analysis system in reference to histopathological results

AIM OF THE STUDY: To retrospectively evaluate how the International Ovarian Tumor Analysis (IOTA) simple rules used in ultrasound examinations estimate the probability of malignant and benign tumour occurrence in the studied population. MATERIAL AND METHODS: The study was performed on a group of 425 patients with ovarian tumours operated in the Clinic of Surgical and Oncological Gynecology at the Medical University of Lodz in the years 2014-2015. Adnexal tumours were rated according to IOTA simple rules, classifying them as probably malignant, probably benign, or unclassified. The results of the study were compared with final histopathological results. The statistical analysis was performed using STATISTICA 13 PL with Medical Pack. RESULTS: We analysed data on n = 43 (11%) patients with malignant, n = 346 (86%) patients with benign, and n = 12 (3%) patients with borderline tumours, respectively. Malignant tumour patients were significantly older (mean age 61.0 ±11.6 vs. 43.6 ±16.2 years, p< 0.001), had higher BMI (mean 27.3 ±7.0 vs. 25.2 ±5.2, p< 0.05), more pregnancies (median 2 vs. 1, p = 0.001), and higher cancer antigen 125 (CA 125) concentrations (median 251.5 vs. 18.5, p< 0.001) than patients with a benign tumour. Also, they more often suffered from diabetes mellitus (19% vs. 8%, p = 0.02) and arterial hypertension (60% vs. 42%, p< 0.01) than benign tumour patients. CONCLUSIONS: In our study, IOTA performance in predicting or ruling out a malignant tumour was highly satisfactory and similar to that of CA 125. Both the methods may be complementary and used to assess the risk of malignant vs. benign ovarian neoplasm, although the context of other clinical variables may also be important.