Intraluminal Uterine Hypodensity in CT Scans of Postmenopausal Women: Recommendations for Interpretation.

OBJECTIVE: This study aims to investigate the association between intraluminal uterine hypodensity and uterine malignancy and establish thresholds that would minimize routine gynecological evaluation.

METHODS: Two groups were recruited retrospectively: cancer group, which comprised 32 sequential endometrial cancer patients, and postmenopausal group, which comprised 63 women, with no known gynecologic malignancy.Two radiologists independently measured hypodensity, transversely in the axial plane and anterioposteriorly in the sagittal plane.The association between cancer and hypodensity was evaluated. Receiver operating characteristic curves were evaluated diameters predictive of cancer.

RESULTS: Hypodensity was associated with cancer (cancer group, 93.8% vs. postmenopausal group, 38.1%; P < 0.0001). Hypodensity diameters correlated highly with prediction of cancer (transverse area under the curve, 0.899; anteroposterior area under the curve, 0.892). Diameters of 19.5 mm transverse and 6.0 mm anteroposterior yielded a sensitivity of 87% and 83% and specificity of 91% and 83%, respectively.

CONCLUSIONS: Intrauterine hypodensity is a common finding in computed tomography scans of postmenopausal women. A transverse diameter of 19.5 mm and an anteroposterior diameter of 6.0 mm are suggested as thresholds for further gynecological sonographic evaluation.