Predictive Value of Conventional Ultrasound and Contrast-Enhanced Ultrasound in Early Recurrence of Hepatocellular Carcinoma after Surgical Resection

Abstract

The goals of the work described here were to study the pre-operative risk factors associated with early recurrence (ER) of hepatocellular carcinoma (HCC) after surgical resection and discuss the value of conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) in predicting ER of HCC, so as to provide more information for optimizing clinical treatment and improving prognosis. A retrospective analysis was conducted on 59 patients who underwent both US and CEUS examinations pre-operatively and surgical resection for HCC between December 2010 and January 2014 in our hospital. The patients' clinical data, laboratory examination data and ultrasonic imaging diagnostic data were collected. Univariate analysis and logistic regression analysis were performed to determine the independent risk factors for ER of HCC after surgical resection. Diagnostic values of independent risk factors in predicting ER were further evaluated. The 59 patients were divided into the ER group (27 cases) and ER-free group (32 cases). There were no significant differences in age and sex between the two groups (p > 0.05). Univariate analysis revealed that differences in pre-operative serum α-fetoprotein level ≥400 ng/mL (p = 0.008), tumor diameter ≥5 cm (p = 0.012), macroscopic vascular invasion (p = 0.040), "fast wash-out" enhancement pattern (p = 0.006) and inhomogeneous distribution of contrast agent (p = 0.031) statistically significantly differed between the two groups. Logistic regression analysis indicated that pre-operative serum AFP level ≥400 ng/mL (p = 0.024), tumor diameter ≥5 cm (p = 0.042) and "fast wash-out" enhancement pattern (p = 0.009) were independent risk factors for ER of HCC; macrovascular invasion (p = 0.095) and inhomogeneous distribution of contrast agent (p = 0.628) did not statistically significantly differ between two groups (p = 0.628). Predictive values of the independent risk factors were further evaluated. The sensitivity of a "fast wash-out" enhancement pattern in predicting ER of HCC post-operatively did not statistically differ from that of tumor diameter ≥5 cm (p > 0.05), whereas it was significantly higher than the sensitivities of the other predictive indexes (p < 0.05). A pre-operative serum α-fetoprotein level ≥400 ng/mL, tumor diameter ≥5 cm and "fast wash-out" enhancement pattern are independent risk factors for ER of HCC after surgical resection. In addition, the "fast wash-out" enhancement pattern could probably be used to screen populations at high risk of recurrence owing to its high sensitivity in predicting ER of HCC post-operatively. All these findings provide beneficial information for management of HCC.

Keywords: Contrast-enhanced ultrasound; Hepatocellular carcinoma; Recurrence; Risk factor; Ultrasound.