International Ovarian Tumour Analysis (IOTA) Phase 5

Validation of ADNEX and IOTA two‐step strategy and estimation of risk of complications during follow‐up of adnexal masses in low‐risk population

ABSTRACTObjectivesTo evaluate the ability of the Assessment of Different NEoplasias in the adneXa (ADNEX) model and the International Ovarian Tumour Analysis (IOTA) two‐step strategy to predict malignancy in adnexal masses detected in an outpatient low‐risk setting, and to estimate the risk of complications in masses with benign ultrasound morphology managed using clinical and ultrasound follow‐up.MethodsThis single‐center study was performed at Hospital Universitari Dexeus, Barcelona, Spain, using interim data from the ongoing prospective observational IOTA Phase‐5 (IOTA5) study. The primary aim of the IOTA5 study is to describe the cumulative incidence of complications during follow‐up of adnexal masses classified as benign on ultrasound examination. Consecutive patients with an adnexal mass detected between June 2012 and September 2016 in a private center offering screening for gynecological cancer were included and followed up until February 2020. Tumors were classified as benign or malignant based on histology (if patients underwent surgery) or the outcome of clinical and ultrasound follow‐up at 12 (range, 10–14) months. Multiple imputation was used when outcomes were uncertain. The ability of the ADNEX model without CA125 and of the IOTA two‐step strategy to distinguish benign from malignant masses was evaluated retrospectively using the prospectively collected data. We assessed performance with regard to discrimination (area under the receiver‐operating‐characteristics curve (AUC)), calibration, classification (sensitivity and specificity) and clinical utility (Net Benefit). In the group of patients with a mass judged to be benign who were selected for conservative management, we evaluated the occurrence of spontaneous resolution or any mass complication during the first 5 years of follow‐up by assessing the cumulative incidence of malignancy, torsion, cyst rupture and minor mass complications (inflammation, infection or adhesions) and the time to occurrence of an event.ResultsA total of 2654 patients were recruited to the study. After application of exclusion criteria, 2039 patients with a newly detected mass were included for the model validation. Of those, 1684 (83%) masses were benign, 49 (2%) masses were malignant and, for 306 (15%) masses, the outcome was uncertain and therefore imputed. The AUC was 0.95 (95% CI, 0.89–0.98) for ADNEX without CA125 and 0.94 (95% CI, 0.88–0.97) for the two‐step strategy. Calibration performance could not be meaningfully interpreted because the small number of malignancies resulted in very wide confidence intervals. The two‐step strategy had better clinical utility than did the ADNEX model at malignancy risk thresholds < 3%. There were 1472 (72%) patients whose mass was judged to be benign based on pattern recognition by an experienced ultrasound examiner and were managed with clinical and ultrasound follow‐up. In this group, the 5‐year cumulative incidence was 66% (95% CI, 63–69%) for spontaneous resolution of the mass, 0% (95% CI, 0–0.2%) for torsion, 0.1% (95% CI, < 0.1–0.4%) for cyst rupture, 0.2% (95% CI, 0.1–0.6%) for a borderline tumor and 0.2% (95% CI, 0.1–0.6%) for invasive malignancy.ConclusionsThe ADNEX model and IOTA two‐step strategy performed well to distinguish benign from malignant adnexal masses detected in a low‐risk population. Conservative management is safe for masses with a benign ultrasound appearance in this population. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Comparison of the ADNEX and ROMA risk prediction models for the diagnosis of ovarian cancer: a multicentre external validation in patients who underwent surgery

Several diagnostic prediction models to help clinicians discriminate between benign and malignant adnexal masses are available. This study is a head-to-head comparison of the performance of the Assessment of Different NEoplasias in the adneXa (ADNEX) model with that of the Risk of Ovarian Malignancy Algorithm (ROMA). This is a retrospective study based on prospectively included consecutive women with an adnexal tumour scheduled for surgery at five oncology centres and one non-oncology centre in four countries between 2015 and 2019. The reference standard was histology. Model performance for ADNEX and ROMA was evaluated regarding discrimination, calibration, and clinical utility. The primary analysis included 894 patients, of whom 434 (49%) had a malignant tumour. The area under the receiver operating characteristic curve (AUC) was 0.92 (95% CI 0.88-0.95) for ADNEX with CA125, 0.90 (0.84-0.94) for ADNEX without CA125, and 0.85 (0.80-0.89) for ROMA. ROMA, and to a lesser extent ADNEX, underestimated the risk of malignancy. Clinical utility was highest for ADNEX. ROMA had no clinical utility at decision thresholds <27%. ADNEX had better ability to discriminate between benign and malignant adnexal tumours and higher clinical utility than ROMA. clinicaltrials.gov NCT01698632 and NCT02847832.