Utility of contrast-enhanced ultrasound with perflubutane for diagnosing the macroscopic type of small nodular hepatocellular carcinomas.

OBJECTIVE

To clarify the diagnostic value of contrast-enhanced ultrasound (CEUS) with perflubutane in the macroscopic classification of small nodular hepatocellular carcinomas (HCCs).

METHODS

A total of 99 surgically resected nodular HCCs with a maximum diameter of 3 cm or less were analysed. HCCs were macroscopically categorized as simple nodular (SN) and non-SN. CEUS findings were evaluated during the arterial phase (vascularity, level and shape of enhancement), portal phase (presence or absence of washout) and post-vascular phase (echo intensity and shape).

RESULTS

Sixty-eight HCCs were categorized as SN and the remaining 31 were categorized as non-SN. For diagnosis of non-SN HCC, the areas under the receiver operating characteristic curve (A z) value for the shape of enhancement in the late arterial phase and the shape of the post-vascular image were 0.824 (95 % confidence interval [CI] 0.721-0.895) and 0.878 (95 % CI 0.788-0.933), respectively. The A z value for the combination of the shape of enhancement in the late arterial phase and the shape of the post-vascular image for the diagnosis of non-SN HCC was 0.907 (95 % CI 0.815-0.956), corresponding to a high diagnostic value.

CONCLUSION

CEUS can provide high-quality imaging assessment for determining the macroscopic classification of small nodular HCCs.

KEY POINTS

• Non-SN is one of the poor prognostic factors in patients with HCC • Assessment of macroscopic type provides valuable information for the management of HCC • CEUS can provide high-quality imaging assessment for macroscopic classification of HCC • For non-SN HCC diagnosed using CEUS, hepatectomy is preferred as curative treatment.