Added Value of Contrast-Enhanced CT for Risk Stratification of Patients With Epithelial Ovarian Tumors Categorized as O-RADS US 4 and 5.

OBJECTIVE: To evaluate the diagnostic performance of contrast-enhanced CT (CE-CT) in restratifying epithelial ovarian tumors (EOTs) among high-risk patients categorized as Ovarian-Adnexal Reporting and Data System (O-RADS) 4 or 5 on ultrasound (US). METHODS: This retrospective study included patients with pathologically confirmed EOTs who underwent preoperative transvaginal US and abdominopelvic CE-CT between September 2017 and December 2022. Lesions were classified into benign, borderline, or malignant categories according to O-RADS lexicon-based CT morphologic and enhancement features. Diagnostic performance parameters, including sensitivity, specificity, positive predictive value, negative predictive value, and accuracy, were calculated on both patient and lesion levels, and interreader agreement was assessed using Cohen's κ. The McNemar's test with continuity correction was used to compare the diagnostic performance of CE-CT and US for discriminating between borderline ovarian tumors and invasive carcinomas after excluding patients with benign EOTs. RESULTS: A total of 210 women (mean age, 48.2 ± 14.2 years) with 258 adnexal lesions were analyzed. At the lesion level, the overall predictive accuracy of CE-CT was 88.8% (229 of 258; 95% confidence interval [CI]: 84.3%-92.1%). Among O-RADS 4 and 5 lesions, CE-CT demonstrated an accuracy of 87.5% (95% CI: 80.7%-92.2%) and 90.0% (117 of 130; 95% CI: 83.6%-94.1%), respectively. At the patient level, CE-CT achieved higher diagnostic accuracy than US (89.3%; 95% CI: 84.0%-92.9% versus 72.0%; 95% CI: 65.2%-78.0%) when excluding patients with benign EOTs. CONCLUSION: CE-CT provides added diagnostic value in restratifying patients with EOTs who are categorized as O-RADS 4 or 5, aiding in characterizing adnexal lesions and supporting more individualized surgical planning.