Detection of hypervascular hepatocellular carcinoma: Comparison of multi-detector CT with digital subtraction angiography and Lipiodol CT

Abstract

Aim: The purpose of this study was to compare the diagnostic accuracy of biphasic multi-detector row helical computed tomography (MDCT), digital subtraction angiography (DSA) and Lipiodol computed tomography (CT) in detection of hypervascular hepatocellular carcinoma (HCC).

Methods: Twenty-eight patients with nodular HCC underwent biphasic MDCT examination: hepatic arterial phase (HAP) 25 s and portal venous phase (PVP) 70 s after injection of the contrast medium (1.5 mL/kg). They also underwent hepatic angiography and intra-arterial infusion of iodized oil. Lipiodol CT was performed 3-4 wk after infusion. MDCT images were compared with DSA and Lipiodol CT images for detection of hepatic nodules.

Results: The three imaging techniques had the same sensitivity in detecting nodules >20 mm in diameter. There was no significant difference in the sensitivity among HAP-MDCT, Lipiodol CT and DSA for nodules of 10-20 mm in diameter. For the nodules <10 mm in diameter, HAP-MDCT identified 47, Lipiodol CT detected 27 (chi2 = 11.3, P = 0.005<0.01, HAP-MDCT vs Lipiodol CT) and DSA detected 16 (chi2 = 9.09, P = 0.005<0.01 vs Lipiodol CT and chi2 = 29.03, P = 0.005<0.01vs HAP-MDCT). However, six nodules <10 mm in diameter were detected only by Lipiodol CT.

Conclusion: MDCT and Lipiodol CT are two complementary modalities. At present, MDCT does not obviate the need for DSA and subsequent Lipiodol CT as a preoperative examination for HCC.

Figure 1

Diagram of nodule detectability by each imaging technique.

Figure 2

A hepatocellular carcinoma nodule identified by Lipiodol CT but not by biphasic MDCT in a 53-year-old man. A: MDCT scan during the arterial phase shows a 3-cm hypervascular tumor in S5 (arrowhead); B: DSA confirms the MDCT findings (arrowhead); C: Lipiodol CT identifies another tumor in S6 (arrowhead) in addition to S5.