Surgically staged focal liver lesions: accuracy and reproducibility of dual-phase helical CT for detection and characterization

Abstract

Purpose: To assess the accuracy and reproducibility of dual-phase helical computed tomography (CT) in enabling preoperative detection and characterization of surgically staged focal liver lesions.

Materials and methods: Surgically and histopathologically proven liver lesions were evaluated by three experienced CT readers. These lesions were present in 77 patients who underwent dual-phase helical CT. Images were interpreted separately by the three blinded reviewers. Each lesion was graded on a nine-point scale of confidence, with 1 being definitely benign, 9 being definitely malignant, and 5 being indeterminate. The chi2 test was used to determine if the distribution of lesion classifications was different between readers.

Results: There was a total of 237 lesions: 73 were benign and 164 were malignant. Sensitivity for lesion detection was 69%, 70%, and 71% for the three reviewers, respectively. Specificity was 91%, 86%, and 90%, and the area under the curve for the alternative-free response receiver operating characteristic curve was 0.84, 0.83, and 0.85, respectively. The difference in the distributions of lesion classification between the three reviewers was not statistically significant (P =.67) as determined by chi2 analysis.

Conclusion: Dual-phase CT has sensitivity of 69%-71% and high specificity (86%-91%) in enabling the detection and characterization of focal liver lesions. Interpretation is highly reproducible, as there is minimal variation between experienced reviewers.