Pre-operative detection of malignant hepatic tumours: value of combined helical CT during arterial portography and biphasic CT during hepatic arteriography.

AIMS

The purpose of our study was to evaluate the observer performance with combined helical CT during arterial portography (CTAP) and biphasic CT hepatic arteriography (CTHA) in the pre-operative detection of malignant hepatic tumours.

METHODS

Computed tomography images obtained in 41 patients with suspected hepatic tumours were retrospectively reviewed. In a blind fashion, three off-site, independent radiologists reviewed CTAP and early-phase CTHA combined for the first review, then late-phase CTHA was added for the second review. Statistical analysis was conducted on lesion-by-lesion and segment-by-segment bases; a total of 328 liver segments including 65 segments with 74 malignant hepatic tumours ranging in size from 5 to 100 mm (mean, 21.4 mm) were analysed.

RESULTS

Sensitivity for detection of liver segments harbouring tumours of CTAP and biphasic CTHA combined (82%) was identical to that of CTAP and early-phase CTHA combined (82%). Specificity of CTAP and biphasic CTHA combined (93%) was greater than that of CTAP and early-phase CTHA combined (90%, P < 0.005). The mean confidence level for the 74 tumours significantly increased by adding late-phase CTHA (P < 0.0005). The mean confidence level for 100-142 benign perfusion abnormalities detected with CTAP and early-phase CTHA combined significantly decreased by adding late-phase CTHA (P < 0.0005).

CONCLUSION

By combining late-phase CTHA with CTAP and early-phase CTHA information, the specificity for the detection of malignant hepatic tumours rises significantly, allowing more accurate preoperative tumour detection.