Diagnostic Performance Of Contrast-enhanced Ultrasound For Hepatocellular Carcinoma

Objective: To investigate the diagnostic performance of contrast-enhanced ultrasound(CEUS)for hepatocellular carcinoma(HCC).Methods: Archives of 500 patients who underwent CEUS examination of focal liver lesions(FLLs)in our hospital from January 2018 to December 2019 were recruited.Target patients with FLL(s)were selected according to certain exclusion criteria and inclusion criteria,and relevantdata were collected and analyzed,including patient’s age,gender,underline diseases such as cirrhosis and chronic hepatitis B,laboratory tests such as tumor markers,ultrasound imaging,CT,MRI,treatment and follow-up results,etc.The assumed diagnoses based on ultrasound and CEUS assessments were compared with the final diagnosis concluded from histopathology,contrast-enhanced CT/MRI,follow-up or comprehensive evaluation,The sensitivity,specificity,accuracy,the area under a receiver operating characteristic(ROC)curve(AUC),positive predictive value and negative predictive value of CEUS for the diagnosis of HCC were calculated,and enhancement models of CEUS of FLLs were analyzed,including onset time of enhancement,washout time,enhancement level in arterial,venous and late phase,etc.The causes and unfavorable factors affecting the CEUS evaluation were probed,and the relevant results were statistically analyzed.Results: A total of 220 patients with FLLs were included in the study,including 99 patients with HCC(86 males,with a mean±standard deviation age of 58.1±12.8 years,13 females,with a mean age of 59.8±5.9 years),and HCC size was 44.9±29.9mm;: 10 patients with ICC;15 patients with liver metastatic carcinoma;two patients with other malignant lesions(hepatosarcoma,small round cell tumor);26 patients with cavernous hemangioma,12 patients with focal nodular hyperplasia,and 56 patients with other parts of benign lesions.Of the CEUS evaluation,97 of 220 FLLs assumed diagnosed as HCC were confirmed to be HCC,two FLLs assumed diagnosed as HCC were confirmed to be non-HCC(one FLL is hyperplastic nodule,and the another FLL is cavernous hemangioma with arteriovenous fistula),eight other FLLs assumed diagnosed as HCC were confirmed to be non-HCC of benign and malignant lesions(one ICC,two metastatic carcinoma,four benign hyperplastic nodules,one cavernous hemangioma),other 113 of 220 FLLs assumed diagnosed as non-HCC of benign and malignant lesions were confirmed to be non-HCC of benign and malignant lesions..99 patients with HCC had underline diseases of chronic hepatitis or cirrhosis.The mean diameter of the tumor of HCC was 44.9mm(13-142mm),15 HCC with diameter < 20 mm,84 HCC with diameter ≥20mm,32 HCC with histopathological diagnosis,diagnoses of other 67 HCC were established according to enhanced CT/MRI,,laboratory examination,follow-up andcomprehensive analysis.AFP increased(≥400ng/m L)in 37 patients with HCC.The onset time of wash-out of the contrast agent was(54s-325s)and(25s-178s)in 99 HCC and 10 ICC,with the mean values of(153.1±78.1)s and(54.4±32.6)s,respectively.Among the99 HCC,except four HCC with no discernable occurred wash-out(iso-enhancement),two(2.1%)of the remaining 95 HCC occurred wash-out before60 s,other 93 HCCs(93.9%)occurred wash-out after 60 s.Five(50.0%)of the 10 ICC occurred wash-out before 60 s.The difference proportions of onset time of wash-out between HCCs and ICCs were statistically significant(P<0.001).The sensitivity,specificity,positive predictive value,negative predictive value,and accuracy of CEUS for the diagnosis of HCC were 98.0%(92.9%-99.8%),93.4%(87.4%-97.1%),92.4%(85.5 %-96.7 %),98.3%(93.9 %-99.8%)and 95.5%(91.7%-97.6%),respectively.The AUC was 95.7%(92.6 %-98.7%).Conclusions: CEUS can distinguish benign from malignant lesions in the evaluation of FLLs.It has high sensitivity,specificity,positive predictive value,negative predictive value,and accuracy for the diagnosis of HCC.FLLs with atypical enhancement models are the main challenge to physicians,which often lead to improper interpretation and misdiagnosis.Attention to onset time of wash-out has great benefit for differential diagnosis of HCC and ICC.Adoption of CEUS has improved and extended the application of ultrasound imaging in clinical practice,and enhanced doctors’ confidence in understanding the benign and malignant focal liver lesions.