Does dual-energy CT differentiate benign and malignant ovarian tumours?

Abstract

To assess the ability of dual-energy computed tomography (DECT) to distinguish benign from malignant ovarian tumours (OTs). Following approval of the institutional review board, the institutional database was mined for treatment-naive patients who underwent primary cytoreduction for OT. Thirty-seven patients were included and divided into those with benign OTs (n=11) and malignant OTs (n=26), including high-grade (n=20) and low-grade (n=6) malignant OTs. Advanced processing and region of interest delineation on the ovarian mass were performed using the preoperative staging DECT examination using the Advantage Workstation. The pixel-level data of the CT attenuation values at 50, 70, and 120 keV and the effective atomic number (Zeff), water content (WC), and iodine content (IC) in the ovarian mass were recorded. The Wilcoxon rank-sum test was used to compare CT attenuation data at different voltages, Zeff, and WC and IC levels between benign and malignant OTs and between high- and low-grade malignant OTs. Simple logistic regression was used to correlate the imaging characteristics with malignant status and grade. Malignant OTs had significantly higher Zeff and IC compared with benign OTs. The threshold values for the diagnosis of malignant OT were IC≥9.74 (100 μg/cm3) with 81% sensitivity and 73% specificity and Zeff ≥8.16 with 85% sensitivity and 73% specificity. High-grade OTs had significantly higher WC compared with low-grade OTs, and a threshold of ≥1,013.92 mg/cm3 differentiated them with 80% sensitivity and 83% specificity. DECT may be a tool to help distinguish malignant and benign OTs and predict tumour grade.