IOTA Simple Rules in Differentiating between Benign and Malignant Adnexal Masses by Non-expert Examiners

Abstract

Objective: To evaluate the diagnostic performance of IOTA simple rules in predicting malignant adnexal tumors by non-expert examiners. Materials and Methods: Five obstetric/gynecologic residents, who had never performed gynecologic ultrasound examination by themselves before, were trained for IOTA simple rules by an experienced examiner. One trained resident performed ultrasound examinations including IOTA simple rules on 100 women, who were scheduled for surgery due to ovarian masses, within 24 hours of surgery. The gold standard diagnosis was based on pathological or operative findings. The five-trained residents performed IOTA simple rules on 30 patients for evaluation of inter-observer variability. Results: A total of 100 patients underwent ultrasound examination for the IOTA simple rules. Of them, IOTA simple rules could be applied in 94 (94%) masses including 71 (71.0%) benign masses and 29 (29.0%) malignant masses. The diagnostic performance of IOTA simple rules showed sensitivity of 89.3% (95%CI, 77.8%; 100.7%), specificity 83.3% (95%CI, 74.3%; 92.3%). Inter-observer variability was analyzed using Cohen's kappa coefficient. Kappa indices of the four pairs of raters are 0.713-0.884 (0.722, 0.827, 0.713, and 0.884). Conclusions: IOTA simple rules have high diagnostic performance in discriminating adnexal masses even when are applied by non-expert sonographers, though a training course may be required. Nevertheless, they should be further tested by a greater number of general practitioners before widely use.

Comparison of the diagnostic accuracy of International Ovarian Tumor Analysis simple rules and the risk of malignancy index to discriminate between benign and malignant adnexal masses

“…However, most studies are confined to a few groups of investigators, and the method is rarely tested by other groups for external validation, especially in other regions of the world. Our team has been studying the IOTA rules for more than eight years and has found the method to be reproducible in our population of Thai women, even among nonspecialist examiners, although performance may not be as high as reported by the pioneers.…”

“…The IOTA rules were created for clinicians to assist in the identification of ultrasound features suggesting malignancy (M‐features) or benignity (B‐features). We have found that, in our population, the IOTA rules can be used effectively by nonspecialist sonographers . Recently, the IOTA rules have increased in popularity.…”

“…The present study was a secondary analysis of our prospective database project ongoing at Maharaj Nakorn Chiang Mai Hospital, Chiang Mai University, with ethical approval from the institutional review board of Chiang Mai University (OBG‐2561‐05364). The database includes the records of patients admitted for elective pelvic surgery for adnexal masses between April 2010 and March 2018.…”

“…Recently, the IOTA rules have increased in popularity. Our prospective database of preoperative ultrasound adnexal mass images has been ongoing for more than eight years . However, performance of the IOTA simple rules has rarely been compared with other systems, such as RMI, in the same study group.…”

Validation of the Performance of International Ovarian Tumor Analysis (IOTA) Methods in the Diagnosis of Early Stage Ovarian Cancer in a Non-Screening Population

“…Our results might not necessarily be applicable to less experienced operators. However, published studies have shown that the IOTA SRs and ADNEX retain their performance in the hands of less experienced examiners [27,28,35,36,37,38,39,40,41]. This is likely to be true also for the SRR model, because the same ultrasound variables are used in the original SRs are used to calculate the risks of the SRR model.…”