Detection of early gastric cancer using hydro-stomach CT:Blinded vs unblinded analysis

AIM:To evaluate the difference in diagnostic performance of hydro-stomach computed tomography(CT) to detect early gastric cancer(EGC) between blinded and unblinded analysis and to assess independent factors affecting visibility of cancer foci.METHODS:Two radiologists initially blinded and then unblinded to gastroscopic and surgical-histological findings independently reviewed hydro-stomach CT images of 110 patients with single EGC.They graded the visibility of cancer foci for each of three gastric segments(upper,middle and lower thirds) using a 4-point scale(1:definitely absent,2:probably absent,3:probably present,and 4:definitely present).The sensitivity and specificity for detecting an EGC were calculated.Intraobserver and interobserver agreements were analyzed.The visibility of an EGC was evaluated with regard to tumor size,invasion depth,gastric segments,histological type and gross morphology using univariate and multivariate analysis.RESULTS:The respective sensitivities and specificities [reviewer 1:blinded,20%(22/110) and 98%(215/220);unblinded,27%(30/110) and 100%(219/220)/reviewer 2:blinded,19%(21/110) and 98%(216/220);unblinded,25%(27/110) and 98%(215/220)] were not significantly different.Although intraobserver agreements were good(weighted κ = 0.677 and 0.666),interobserver agreements were fair(blinded,0.371) or moderate(unblinded,0.558).For both univariate and multivariate analyses,the tumor size and invasion depth were statistically significant factors affecting visibility.CONCLUSION:The diagnostic performance of hydrostomach CT to detect an EGC was not significantly different between blinded and unblinded analysis.The tumor size and invasion depth were independent factors for visibility.

Current status of radiofrequency ablation of hepatocellular carcinoma

Loco-regional treatments for hepatocellular carcinoma(HCC) are important alternatives to curative transplantation or resection.Among them,radiofrequency ablation(RFA) is accepted as the most popular technique showing excellent local tumor control and acceptable morbidity.The current role of RFA is well documented in the evidence-based practice guidelines of European Association of Study of Liver,American Association of Study of the Liver Disease and Japanese academic societies.Several randomized controlled trials have confirmed that RFA is superior to percutaneous ethanol injections in terms of local tumor control and survival.The overall survival after RFA is comparable to after surgical resection in a selected group of patients with smaller(< 3 cm) tumors.Currently,the clinical benefits of combined RFA with transarterial chemoembolization for intermediate stage HCC are increasingly being explored.Here we review the ongoing technical advancements of RFA and future potential.

Concurrent and subsequent radiofrequency ablation combined with hepatectomy for hepatocellular carcinomas

Partial hepatectomy has long been the standard treatment modality for patients with hepatocellular carcinoma(HCC),although the majority of patients with HCCs are not candidates for curative resection.Radiofrequency ablation(RFA) has been widely used as the preferred locoregional therapy.RFA and hepatectomy can be complementary to each other for the treatment of multifocal HCCs.Combining hepatectomy with RFA permits the removal of larger tumors while simultaneously ablating any smaller residual tumors.By using this combination treatment,more patients might become candidates for curative resection.For treating recurrent tumors involving the liver after hepatectomy,RFA has been performed recently instead of transcatheter arterial chemoembolization or ethanol ablation.Many retrospective studies on the combination of RFA and hepatectomy demonstrate favorable results of effectiveness and safety.However,further investigation of prospective design will be needed to confirm these encouraging results.

High-risk esophageal varices in patients treated with locoregional therapy for hepatocellular carcinoma:Assessment with liver computed tomography

AIM:To assess the diagnostic performance of followup liver computed tomography(CT) for the detection of high-risk esophageal varices in patients treated with locoregional therapy for hepatocellular carcinoma(HCC).METHODS:We prospectively enrolled 100 patients with cirrhosis who underwent transcatheter arterial chemoembolization,radiofrequency ablation or both procedures for HCCs.All patients underwent upper endoscopy and subsequently liver CT.Three radiologists independently evaluated the presence of high-risk esophageal varices with transverse images alone and with three orthogonal multiplanar reformation(MPR) images,respectively.With endoscopic grading as the reference standard,diagnostic performance was assessed by using receiver operating characteristic(ROC) curve analysis.RESULTS:The diagnostic performances(areas under the ROC curve) of three observers with transverse images alone were 0.947 ± 0.031,0.969 ± 0.024,and 0.916 ± 0.038,respectively.The mean sensitivity,specificity,positive predicative value(PPV),and negative predicative value(NPV) with transverse images alone were 90.1%,86.39%,70.9%,and 95.9%,respectively.The diagnostic performances,mean sensitivity,specificity,PPV,and NPV with three orthogonal MPR images(0.965 ± 0.025,0.959 ± 0.027,0.938 ± 0.033,91.4%,89.5%,76.3%,and 96.6%,respectively) were not superior to corresponding values with transverse images alone(P > 0.05),except for the mean specificity(P = 0.039).CONCLUSION:Our results showed excellent diagnostic performance,sensitivity and NPV to detect high-risk esophageal varices on follow-up liver CT after locoregional therapy for HCC.