Efficacy of contrast-enhanced ultrasound washout rate in predicting hepatocellular carcinoma differentiation.
The aim of this retrospective study was to evaluate the efficacy of contrast-enhanced ultrasound (CEUS) washout rate in predicting hepatocellular carcinoma (HCC) differentiation. Two hundred seventy-one patients underwent liver resection for HCC between April 2008 and December 2012 after being examined by CEUS using the contrast agent SonoVue with a low mechanical index (<0.1) in a routine procedure. Contrast agent washout rates obtained from video images were divided into four categories from slow to fast: WR1 = no washout in all phases (slowest); WR2 = washout after 120 s from contrast injection (late-phase washout); WR3 = washout between 41 and 120 s from contrast injection (portal venous washout); WR4 = washout before 40 s from contrast injection (fastest washout rate). HCC nodules were graded as well, moderately and poorly differentiated. Spearman rank correlation and χ(2)-tests were used to assess group relationships and differences. Receiver operating characteristic curve analysis was used to determine the diagnostic predictive value of CEUS. Among the 271 patients, 18 (6.6%) had well differentiated, 150 (55.4%) had moderately differentiated and 103 (38.0%) had poorly differentiated HCC. Statistical tests indicated that washout rate was significantly correlated with tumor differentiation (p < 0.05), and the poorly differentiated HCCs had earlier washout. At the cutoff point of WR4, CEUS based on washout rate performed poorly in distinguishing poorly differentiated from moderately and well-differentiated HCCs, with a sensitivity, specificity and accuracy (area under the curve) of 24%, 97% and 0.68, respectively. However, at the cutoff point of WR2, the sensitivity, specificity and accuracy of CEUS in differentiating well-differentiated HCC from other HCCs were significantly better: 98%, 78% and 0.96, respectively. Thus, CEUS washout rate may have a role in identifying patients with well-differentiated HCC.
Ultrasound Department, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China; Medical Imaging Pharmaceutical Lab, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
Yan
Y
Feng
Ultrasound Department, Nanchong Central Hospital, Nanchong, Sichuan Province, China.
Xia-Chuan
XC
Qin
Ultrasound Department, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
Yan
Y
Luo
Ultrasound Department, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
Yong-Zhong
YZ
Li
Ultrasound Department, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China; Medical Imaging Pharmaceutical Lab, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China. Electronic address: Zhou.xiang@yeah.net.
Xiang
X
Zhou
D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000493:pharmacokinetics*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008099:Liver / Q000000981:diagnostic imaging; D008113:Liver Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010743:Phospholipids / Q000493:pharmacokinetics*; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013459:Sulfur Hexafluoride / Q000493:pharmacokinetics*; D014463:Ultrasonography; D055815:Young Adult
D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride
Contrast-enhanced ultrasound imaging; Differentiation; Hepatocellular carcinoma; Prognosis; Washout rate