New OPTN/UNOS policy for liver transplant allocation: standardization of liver imaging, diagnosis, classification, and reporting of hepatocellular carcinoma

Y90 Radioembolization Significantly Prolongs Time to Progression Compared With Chemoembolization in Patients With Hepatocellular Carcinoma

BACKGROUND & AIMS

Conventional transarterial chemoembolization (cTACE) is used to treat patients with hepatocellular carcinoma (HCC). Radioembolization is a minimally invasive procedure that involves implantation of radioactive micron-sized particles loaded with yttrium-90 (Y90) inside the blood vessels that supply a tumor. We performed a randomized, phase 2 study to compare the effects of cTACE and Y90 radioembolization in patients with HCC.

METHODS

From October 2009 through October 2015, we reviewed patients with HCC of all Barcelona Clinic Liver Cancer (BCLC) stages for eligibility. Of these, 179 patients with BCLC stages A or B met our enrollment criteria and were candidates for cTACE or Y90 therapy. Patients were assigned randomly to groups that received Y90 therapy (n = 24; 50% Child-Pugh A) or cTACE (n = 21; 71% Child-Pugh A). The primary outcome was time to progression (TTP), evaluated by intention-to-treat analysis. Secondary outcomes included safety, rate of response (based on tumor size and necrosis criteria), and Kaplan-Meier survival time. We performed inverse probability of censoring weighting and competing risk analyses.

RESULTS

Patients in the Y90 radioembolization group had significant longer median TTP (>26 mo) than patients in the cTACE group (6.8 mo; P = .0012) (hazard ratio, 0.122; 95% confidence interval [CI], 0.027-0.557; P = .007). This was confirmed by competing risk and inverse probability of censoring weighting analyses accounting for transplantation or death. A significantly greater proportion of patients in the cTACE group developed diarrhea (21%) than in the Y90 group (0%; P = .031) or hypoalbuminemia (58% in the cTACE group vs 4% in the Y90 group; P < .001). Similar proportions of patients in each group had a response to therapy, marked by necrosis (74% in the cTACE group vs 87% in the Y90 group) (P = .433). The median survival time, censored to liver transplantation, was 17.7 months for the cTACE group (95% CI, 8.3-not calculable) vs 18.6 months for the Y90 group (95% CI, 7.4-32.5) (P = .99).

CONCLUSIONS

In a randomized phase 2 study of patients with HCC of BCLC stages A or B, we found Y90 radioembolization to provide significantly longer TTP than cTACE. Y90 radioembolization provides better tumor control and could reduce drop-out from transplant waitlists. ClinicalTrials.gov no. NCT00956930.

Association of socioeconomics, surgical therapy, and survival of early stage hepatocellular carcinoma

BACKGROUND

Underutilization of potential curative surgical treatment remains a problem in the management of hepatocellular carcinoma (HCC). Demographic and socioeconomic disparities continue to be important factors impacting utilization patterns, and exact mechanisms underlying these disparities remain largely unclarified. Focusing on these mechanisms provides us with a potential approach to improve survival of HCC patients.

METHODS

We performed a retrospective cohort study using the Surveillance, Epidemiology, and End Results Database to assess patients with early stage HCC diagnosed between January 2004 and December 2012. Demographic and socioeconomic factors were analyzed to assess associations with utilization of treatment, stage of presentation, and disease-specific survival by means of multinominal and Cox regression.

RESULTS

A total of 13,694 patients were included in the analysis of which only 6239 (45.6%) underwent surgical treatment for early stage HCC. Surgical treatment options consisted of 1445 liver resections (10.6%), 2121 liver transplantations (15.5%), and 2673 liver ablations (19.5%). The rate of surgical treatment fell from 56.1% in 2004 to 37.8% in 2012. Compared with no surgical therapy, African Americans were less likely to undergo liver transplantation (relative risk ratio [RRR] = 0.54; 95% confidence interval [CI], 0.36-0.79) than Caucasian patients and more likely to undergo surgical resection (RRR = 1.67; 95% CI, 1.13-2.48). Patients from the Pacific West were less likely to be transplanted versus patients from the Southeast (RRR = 0.68; 95% CI, 0.50-0.93). Also, patients who were married (RRR = 2.44; 95% CI, 1.96-3.04) or had health insurance (RRR = 4.74; 95% CI, 1.66-13.6) were more likely to receive liver transplantation. Young age (hazard ratio = 1.02; 95% CI, 1.00-1.03; P = 0.025) and positive marital status (hazard ratio = 0.71; 95% CI, 0.55-0.92; P = 0.010) both were independently associated with increased disease-specific survival.

CONCLUSIONS

An increasing proportion of patients with early stage HCC did not undergo surgical therapy between 2004 and 2012. Demographic and socioeconomic factors were associated with different treatment modality utilization after controlling for available confounders. Of these factors, age and marital status were independently associated with increased disease-specific survival.

Imaging prediction of residual hepatocellular carcinoma after locoregional therapy in patients undergoing liver transplantation or partial hepatectomy

PURPOSE

Locoregional therapies for hepatocellular carcinoma (HCC) offer alternatives for patients unable to undergo resection or awaiting transplant. We sought to evaluate the prevalence and interobserver agreement of imaging features suggestive of viable tumor at posttherapy CT/MRI and to determine a size threshold for tumor detection.

METHODS

Patients having undergone liver transplant or hepatectomy between 2012 and 2014 with presurgical embolization or ablation of HCC were identified. Imaging was retrospectively reviewed, and enhancement characteristics of each lesion were noted by two radiologists. Original pathology slides were reviewed, and the size of nodular viable tumor was noted, if present. Cohen's kappa was used to evaluate interobserver agreement.

RESULTS

87 patients with 129 HCCs were reviewed retrospectively following IRB approval. 50% (65/129) of lesions showed viable tumor at pathology. 86 lesions (67%) were imaged with CT and 43 (33%) with MR. Of viable lesions, 25 (38%) showed nodular arterial enhancement and 18 (28%) demonstrated washout. One lesion had capsule appearance. Sensitivity/specificity for nodular enhancement, washout, and capsule were 0.38/0.83, 0.28/0.89, and 0.02/1.00, respectively. Overall detection rate was 41% of <1 cm, 54% of 1-2 cm, and 57% of >2 cm viable lesions.

CONCLUSIONS

Nodular arterial enhancement was most frequently observed, followed by washout. Both showed moderate interobserver agreement. Sensitivity of any imaging feature was less than 50%, though findings were specific for viable disease. There is limited detection of nodules of viable tumor <1 cm and only marginal detection of larger lesions, though MRI outperformed CT for the detection of subcentimeter viable tumor.

Added value of smooth hypointense rim in the hepatobiliary phase of gadoxetic acid-enhanced MRI in identifying tumour capsule and diagnosing hepatocellular carcinoma

OBJECTIVES

To examine the added value of considering smooth hypointense rim in the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI as capsule appearance for diagnosing tumour capsules and hepatocellular carcinoma (HCC).

METHODS

A total of 377 hepatic lesions (330 HCCs, 35 non-HCC malignancies and 12 benign) were included from 345 patients who underwent resection after MRI between January 2008 and December 2011. Two radiologists assessed the presence or absence of conventional capsule appearance and smooth hypointense rim in the HBP, and categorized each hepatic lesion according to the Liver Imaging Reporting and Data System. Difference in diagnostic performance was evaluated using the generalized estimating equation method.

RESULTS

For identifying capsule, the sensitivity and accuracy of HBP hypointense rim were significantly higher than those of conventional capsule appearance (81.5 % vs. 57.8 % and 76.1 % vs. 59.4 %, respectively; P < 0.001). For diagnosing HCC, the sensitivity and accuracy of LR-5 or LR-5 V were significantly higher when the HBP hypointense rim was also considered capsule appearance (83 % vs. 72.7 % and 84.1 % vs. 75.1 %, respectively; P < 0.001), with the same specificity (91.5 %).

CONCLUSIONS

Regarding smooth hypointense rim in the HBP as capsule appearance could improve the detection of tumour capsule and the diagnosis of HCC.

KEY POINTS

• Identifying tumour capsule is important for diagnosis of hepatocellular carcinoma (HCC). • Gadoxetic acid-enhanced MRI provides hepatobiliary phase (HBP) images. • Smooth hypointense rim seen in HBP may represent tumour capsule. • Regarding smooth hypointense rim as capsule appearance may improve HCC diagnosis.

Hepatocellular carcinoma: a review

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and is a leading cause of cancer-related death worldwide. In the United States, HCC is the ninth leading cause of cancer deaths. Despite advances in prevention techniques, screening, and new technologies in both diagnosis and treatment, incidence and mortality continue to rise. Cirrhosis remains the most important risk factor for the development of HCC regardless of etiology. Hepatitis B and C are independent risk factors for the development of cirrhosis. Alcohol consumption remains an important additional risk factor in the United States as alcohol abuse is five times higher than hepatitis C. Diagnosis is confirmed without pathologic confirmation. Screening includes both radiologic tests, such as ultrasound, computerized tomography, and magnetic resonance imaging, and serological markers such as α-fetoprotein at 6-month intervals. Multiple treatment modalities exist; however, only orthotopic liver transplantation (OLT) or surgical resection is curative. OLT is available for patients who meet or are downstaged into the Milan or University of San Francisco criteria. Additional treatment modalities include transarterial chemoembolization, radiofrequency ablation, microwave ablation, percutaneous ethanol injection, cryoablation, radiation therapy, systemic chemotherapy, and molecularly targeted therapies. Selection of a treatment modality is based on tumor size, location, extrahepatic spread, and underlying liver function. HCC is an aggressive cancer that occurs in the setting of cirrhosis and commonly presents in advanced stages. HCC can be prevented if there are appropriate measures taken, including hepatitis B virus vaccination, universal screening of blood products, use of safe injection practices, treatment and education of alcoholics and intravenous drug users, and initiation of antiviral therapy. Continued improvement in both surgical and nonsurgical approaches has demonstrated significant benefits in overall survival. While OLT remains the only curative surgical procedure, the shortage of available organs precludes this therapy for many patients with HCC.

Quantitative assessment of washout in hepatocellular carcinoma using MRI

Background

Arterial hyperenhancement and washout on computed tomography and magnetic resonance imaging (MRI) are described by all major guidelines as specific criteria for non-invasive diagnosis of hepatocellular carcinoma (HCC). However, publications on the quantitative assessment of washout in MRI are lacking. Therefore, we evaluated a method for quantitatively measuring and defining washout in MRI in order to determine a cutoff value that allows objective HCC diagnosis.

Methods

We analyzed all patients who underwent liver transplantation for cirrhosis or liver resection for HCC at our institution between 2003 and 2014. Washout was quantitatively investigated by placing a 25-mm² region of interest (ROI) over each nodule and two 25-mm² ROIs over adjacent liver parenchyma. The percentage signal ratio (PSR = 100 × ratio of signal intensity of adjacent liver to that of the lesion) was calculated for each series in both groups. Accordingly, this quantitative measurement was compared to a qualitative approach.

Results

A total of 16 hypervascularized non-HCC nodules and 69 HCC nodules were identified. Interobserver reliability was reasonably good for the measurement of PSRs and readers showed a substantial agreement for the qualitative assessment. In the HCC group, the median PSR was 116.2 at equilibrium and 112.9 in the delayed phase. In the non-HCC group, the median PSR was 93.8 at equilibrium and 96.0 in the delayed phase. Receiver operating characteristic analysis indicated areas under the curve of 0.902 (p < 0.001) and 0.873 (p < 0.001) at equilibrium and in the delayed phase. PSR values of 102 at equilibrium and 101.5 in the delayed phase led to the highest Youden’s index of 0.82 and 0.77, respectively. These PSR cutoffs yielded sensitivities of 82 and 77 %, respectively, with specificities of 100 %. The sensitivity for the qualitative assessment of washout was 88 and 93 % and the specificity was 48 and 56 %. For the classification of HCC, sensitivity yielded 95 and 97 % and specificity was 68 and 56 %, respectively.

Conclusion

Quantitatively measuring HCC washout in MRI is easy and reproducible. It can objectify and support diagnosis of HCC. However, the quantitative measurement of washout can only serve as one of several components of HCC assessment.

Reliability, Validity, and Reader Acceptance of LI-RADS-An In-depth Analysis

RATIONALE AND OBJECTIVES

This study aimed to analyze interreader agreement and diagnostic accuracy of Liver Imaging Reporting and Data System (LI-RADS) in comparison to a nonstandardized 5-point scale and to assess reader acceptance of LI-RADS for clinical routine.

MATERIALS AND METHODS

Eighty-four consecutive patients at risk for hepatocellular carcinoma who underwent liver magnetic resonance imaging were included in this Health Insurance Portability and Accountability Act-compliant retrospective study. Four readers rated the likelihood of hepatocellular carcinoma for 104 liver observations using LI-RADS criteria and a 5-point Likert scale (LIKERT) based on subjective impression in two separate reading sessions. Interreader agreement was assessed using kappa statistics (κ). Diagnostic accuracy was assessed with receiver operating characteristic analysis. Reader acceptance was evaluated with a questionnaire. A sub-analysis of LI-RADS's major features (arterial phase hyper-enhancement, washout, capsule appearance, and threshold growth) and scores for lesions </>1.5 cm was performed.

RESULTS

LI-RADS showed similar overall interreader agreement compared to LIKERT (κ, 0.44 [95%CI: 0.37, 0.52] and 0.35 [95%CI: 0.27, 0.43]) with a tendency toward higher interreader agreement for LI-RADS. Interreader agreement (κ) was 0.51 (95%CI: 0.38, 0.65) for arterial phase hyper-enhancement, 0.52 (95%CI: 0.39, 0.65) for washout, 0.37 (95%CI: 0.23, 0.52) for capsule appearance, and 0.50 (95%CI: 0.38, 0.61) for threshold growth. Overall interreader agreement for LI-RADS categories was similar between observations <1.5 cm and observations >1.5 cm. Overall diagnostic accuracy for LIKERT and LI-RADS was comparable (area under the receiver operating characteristic curve, 0.86 and 0.87). Readers fully agreed with the statement "A short version of LI-RADS would facilitate the use in clinical routine" (median, 5.0; interquartile range, 2.25).

CONCLUSIONS

LI-RADS showed similar interreader agreement and diagnostic accuracy compared to nonstandardized reporting. However, further reduction of complexity and refinement of imaging features may be needed.

Natural history of liver imaging reporting and data system category 4 nodules in MRI

PURPOSE

The purpose of this study was to characterize the MR imaging features and outcomes of liver imaging reporting and data system (LI-RADS) category 4 (LR4) nodules, with an emphasis on upgrade to category 5 (LR5) and development of contraindications to curative therapy.

METHODS

Institutional review board approval was obtained for this retrospective, dual-institutional Health Insurance Portability and Accountability Act-compliant study. The requirement for informed consent was waived. Contrast-enhanced MRI studies performed on patients with cirrhosis were retrospectively assessed using LI-RADS 2014 by at least two readers. All nodules were individually evaluated to determine their major imaging features at diagnosis, and follow-up data were used to determine the associated imaging outcomes.

RESULTS

One hundred eighty-one untreated LR4 nodules in 139 patients had adequate imaging and follow-up for inclusion in the study. Most (61% [111/181]) of these demonstrated arterial phase hyperenhancement, washout, and diameter less than 20 mm. During the follow-up period (median 163 days), 31% (56/181) of the nodules upgraded to LR5, 40% (73/181) remained stable, and 29% (52/181) downgraded. Of the nodules that upgraded, 61% (34/56) increased their size category and 54% (30/56) developed newly visualized capsules. No LR4 nodules developed venous invasion, satellites nodules, or new intrahepatic or extrahepatic metastatic disease. 75% (42/56) of the nodules that upgraded to LR5 did so within 6 months.

CONCLUSIONS

Approximately one-third of LR4 nodules upgrade to LR5, and the short-term risk of developing venous invasion or metastasis is very low.

Is there an added value of a hepatobiliary phase with gadoxetate disodium following conventional MRI with an extracellular gadolinium agent in a single imaging session for detection of primary hepatic malignancies?

PURPOSE

To determine added value of hepatobiliary phase (HBP) using gadoxetate disodium compared to MRI with extracellular gadolinium-based contrast agent (GBCA) for detection of primary hepatic malignancies in a single imaging session.

MATERIALS AND METHODS

IRB approved this HIPAA compliant retrospective study. Within 90 days of resection or liver transplant, thirty patients underwent MRI with extracellular GBCA followed by separate injection of gadoxetate for HBP. Two sets of images were reviewed: Set #1-unenhanced and enhanced images with an extracellular GBCA and set #2-with addition of HBP. Data were analyzed in two groups, cases with hepatocellular carcinoma (HCC) only and cases with either HCC and/or cholangiocarcinoma. Observer diagnostic accuracy (Az), sensitivity, and specificity were calculated.

RESULTS

14/30 subjects had HCC (46%, CI 28-66%), 2/30 (2%, CI 1-22%) cholangiocarcinoma, and 14/30 (46%, CI 28-66%) no malignancy. There was no significant change in A z value with addition of gadoxetate in the detection of HCC (range 0.84-0.97 set #1 and 0.85-0.97 set #2, p > 0.05). Sensitivity and specificity showed no significant differences (p > 0.05) between the image sets for all readers. When stratified by lesion size, there was no significant difference in accuracy, sensitivity, or specificity for any reader (p > 0.05).

CONCLUSION

When compared to extracellular GBCA, gadoxetate HBP imaging does not result in a significant difference in accuracy or sensitivity in diagnosis of HCC or cholangiocarcinoma and may result in a decrease in specificity.

Transportal Radioembolization as Salvage Hepatocellular Carcinoma Therapy to Maintain Liver Transplant Candidacy

A 53-year-old woman with chronic hepatitis B and multifocal hepatocellular carcinoma was unable to receive transarterial radioembolization and had disease progression despite multiple chemoembolizations and systemic chemotherapy. Transportal radioembolization (TPRE) to maintain transplant candidacy was performed. Two lesions (1.7 cm, 1.4 cm) were treated with a single session of TPRE. Imaging performed at 4 months after TPRE demonstrated complete response in one lesion and stable disease in the other. This case illustrates TPRE as a salvage therapy for hepatocellular carcinoma in select patients.

Effects of Microwave Ablation on Arterial and Venous Vasculature after Treatment of Hepatocellular Carcinoma

Purpose To characterize vessel occlusion rates and their role in local tumor progression in patients with hepatocellular carcinoma (HCC) who underwent microwave tumor ablation. Materials and Methods This institutional review board approved, HIPAA-compliant retrospective review included 95 patients (75 men and 20 women) with 124 primary HCCs who were treated at a single center between January 2011 and March 2014. Complete occlusion of the portal veins, hepatic veins, and hepatic arteries within and directly abutting the ablation zone was identified with postprocedure contrast material-enhanced computed tomography. For each vessel identified in the ablation zone, its size and antenna spacing were recorded and correlated with vascular occlusion with logistic regression analysis. Local tumor progression rates were then compared between patent and occluded vessels for each vessel type with Fisher exact test. Results Occlusion was identified in 39.7% of portal veins (29 of 73), 15.0% of hepatic veins (six of 40), and 14.2% of hepatic arteries (10 of 70) encompassed within the ablation zone. Hepatic vein occlusion was significantly correlated with a smaller vessel size (P = .036) and vessel-antenna spacing (P = .006). Portal vein occlusion was only significantly correlated with a smaller vessel size (P = .001), particularly in vessels that were less than 3 mm in diameter. Local tumor progression rates were significantly correlated with patent hepatic arteries within the ablation zone (P = .02) but not with patent hepatic (P = .57) or portal (P = .14) veins. Conclusion During microwave ablation of HCC, hepatic veins and arteries were resistant to vessel occlusion compared with portal veins, and only arterial patency within an ablation zone was related to local tumor progression. ^© RSNA, 2016.

Differences in Liver Imaging and Reporting Data System Categorization Between MRI and CT

OBJECTIVE

The purpose of this study is to determine whether focal liver observations are categorized differently by CT and MRI using the Liver Imaging and Reporting Data System (LI-RADS).

MATERIALS AND METHODS

We performed a retrospective review of 58 patients at risk for hepatocellular carcinoma who underwent liver protocol CT and MRI within 1 month of each other. Two readers assigned a LI-RADS category for all focal liver observations in consensus. A significant category upgrade was defined as a change from LI-RADS categories 1 and 2 or nonvisualization to LI-RADS categories 3-5, from LI-RADS category 3 to category 4 or 5, from LI-RADS category 4 to category 5, or from any category to LI-RADS category 5V. A significant downgrade was defined as a change from LI-RADS category 5 to categories 1-4, from LI-RADS category 4 to categories 1-3, or from LI-RADS category 3 to categories 1 or 2.

RESULTS

The LI-RADS category was different between CT and MRI for 77.2% (176/228) of observations. A significant upgrade occurred on MRI for 42.5% (97/228) of observations because of nonvisualization by CT (n = 78), capsule (n = 8), arterial hyperenhancement (n = 4), intratumoral fat (n = 2), larger size (n = 2), tumor in portal vein (n = 2), and wash-out (n = 1). Of these 97 upgraded observations, two were upgraded to LI-RADS category 5V, 15 were upgraded to category 5, and 13 were upgraded to category 4. A significant downgrade occurred on MRI for 8.8% (20/228) of observations because of marked T2 hyperintensity (n = 14), smaller size (n = 2), wedge shape (n = 2), and marked T2 hypointensity (n = 2).

CONCLUSION

LI-RADS categorization of focal liver observations is dependent on imaging modality. MRI results in both upgraded and downgraded categorization compared with CT in an important proportion of observations.

An early look at the Organ Procurement and Transplantation Network explant pathology form data

In April 2012, the Organ Procurement and Transplantation Network (OPTN) implemented an online explant pathology form for recipients of liver transplantation who received additional wait-list priority for their diagnosis of hepatocellular carcinoma (HCC). The purpose of the form was to standardize the data being reported to the OPTN, which had been required since 2002 but were submitted to the OPTN in a variety of formats via facsimile. From April 2012 to December 2014, over 4500 explant forms were submitted, allowing for detailed analysis of the characteristics of the explanted livers. Data from the explant pathology forms were used to assess agreement with pretransplant imaging. Explant data were also used to assess the risk of recurrence. Of those with T2 priority, 55.7% were found to be stage T2 on explant. Extrahepatic spread (odds ratio [OR] = 6.8; P < 0.01), poor tumor differentiation (OR = 2.8; P < 0.01), microvascular invasion (OR = 2.6; P < 0.01), macrovascular invasion (OR = 3.2; P < 0.01), and whether the Milan stage based on the number and size of tumors on the explant form was T4 (OR = 2.4; P < 0.01) were the strongest predictors of recurrence. In conclusion, this analysis confirms earlier findings that showed an incomplete agreement between pretransplant imaging and posttransplant pathology in terms of HCC staging, though the number of patients with both no pretransplant treatment and no tumor in the explant was reduced from 20% to <1%. In addition, several factors were identified (eg, tumor burden, age, sex, region, ablative therapy, alpha-fetoprotein, Milan stage, vascular invasion, satellite lesions, etc.) that were predictive of HCC recurrence, allowing for more targeted surveillance of high-risk recipients. Continued evaluation of these data will help shape future guidelines or policy recommendations. Liver Transplantation 22 757-764 2016 AASLD.

From Child-Pugh to Model for End-Stage Liver Disease: Deciding Who Needs a Liver Transplant

This article reviews the historical evolution of the liver transplant organ allocation policy and the indications/contraindications for liver transplant, and provides an overview of the liver transplant evaluation process. The article is intended to help internists determine whether and when referral to a liver transplant center is indicated, and to help internists to counsel patients whose initial evaluation at a transplant center is pending.

Rate of observation and inter-observer agreement for LI-RADS major features at CT and MRI in 184 pathology proven hepatocellular carcinomas

PURPOSE

To compare frequency and inter-reader agreement for LI-RADS v2014 major features at CT vs. MRI in pathology-proven cases of hepatocellular carcinoma.

METHODS

Pathology reports and imaging studies from patients having undergone liver transplant or hepatectomy for hepatocellular carcinoma were reviewed. Size, location, washout, and capsule appearance for each lesion were recorded by two radiologists. Cohen's kappa and intraclass correlation coefficients (ICC) were calculated.

RESULTS

One hundred and thirty-four patients with 184 tumors were reviewed. Seventy-seven percentage of lesions were imaged by CT and 23% by MRI. No lesions were evaluated with both modalities. Mean lesion diameter was 2.6 ± 1.3 cm (ICC = 0.92). Arterial phase hyperenhancement was seen in 86% of lesions (κ = 0.75). Washout was seen in 82% of studies (κ = 0.61). Arterial phase hyperenhancement and washout were seen equally at CT and MRI (p = 1.00 and 0.46, respectively). Capsule was infrequently observed (27%) but was seen more commonly at MRI (44%) than at CT (17%) with p = 0.002 and (κ = 0.56). Forty-seven percent of lesions with at least one prior study met LI-RADS criteria for threshold growth. The rates of LI-RADS categories 3, 4, and 5 were 9%, 37%, and 54%, respectively. More 1-2 cm LI-RADS 5 lesions were seen at MRI (43%) than at CT (8%), p = 0.01.

CONCLUSION

A combined LI-RADS 4/5 group was 91% sensitive for hepatocellular carcinoma. Arterial enhancement and washout were seen more frequently than capsule, the sole finding seen more frequently at MRI than at CT. Inter-reader reliability was substantial for arterial hyperenhancement and washout but moderate for capsule. Capsule remains an important finding in small arterially enhancing lesions (1-2 cm) which require a second major criterion to upgrade to a LI-RADS 5 lesion.

Imaging Outcomes of Liver Imaging Reporting and Data System Version 2014 Category 2, 3, and 4 Observations Detected at CT and MR Imaging

Purpose To determine the proportion of untreated Liver Imaging Reporting and Data System (LI-RADS) version 2014 category 2, 3, and 4 observations that progress, remain stable, or decrease in category and to compare the cumulative incidence of progression in category. Materials and Methods In this retrospective, longitudinal, single-center, HIPAA-compliant, institutional review board-approved study, 157 patients (86 men and 71 women; mean age ± standard deviation, 59.0 years ± 9.7) underwent two or more multiphasic computed tomographic (CT) or magnetic resonance (MR) imaging examinations for hepatocellular carcinoma surveillance, with the first examination in 2011 or 2012. One radiologist reviewed baseline and follow-up CT and MR images (mean follow-up, 614 days). LI-RADS categories issued in the clinical reports by using version 1.0 or version 2013 were converted to version 2014 retrospectively; category modifications were verified with another radiologist. For index category LR-2, LR-3, and LR-4 observations, the proportions that progressed, remained stable, or decreased in category were calculated. Cumulative incidence curves for progression were compared according to baseline LI-RADS category (by using log-rank tests). Results All 63 index LR-2 observations remained stable or decreased in category. Among 166 index LR-3 observations, seven (4%) progressed to LR-5, and eight (5%) progressed to LR-4. Among 52 index LR-4 observations, 20 (38%) progressed to a malignant category. The cumulative incidence of progression to a malignant category was higher for index LR-4 observations than for index LR-3 or LR-2 observations (each P < .001) but was not different between LR-3 and LR-2 observations (P = .155). The cumulative incidence of progression to at least category LR-4 was trend-level higher for index LR-3 observations than for LR-2 observations (P = .0502). Conclusion Observations classified according to LI-RADS version 2014 categories are associated with different imaging outcomes. (©) RSNA, 2016 Online supplemental material is available for this article.

Diagnostic accuracy of liver imaging reporting and data system (LI-RADS) v2014 for intrahepatic mass-forming cholangiocarcinomas in patients with chronic liver disease on gadoxetic acid-enhanced MRI

PURPOSE

To investigate the utility of Liver Imaging Reporting and Data System (LI-RADS) v2014 for intrahepatic mass-forming cholangiocarcinomas (IMCC) on gadoxetic acid-enhanced magnetic resonance imaging (MRI).

MATERIALS AND METHODS

This retrospective study was approved by our Institutional Review Board with waiver of informed consent. Pathologically confirmed IMCCs (n = 35) and hepatocellular carcinomas (HCCs) (n = 71) in patients with chronic hepatitis B or cirrhosis who had undergone gadoxetic acid-enhanced 3.0T or 1.5T MRI were included. Three radiologists independently assigned LI-RADS categories for each IMCC or HCC. Diagnostic performances of LR-M (probable malignancy, not specific for HCC) and LR-5/5v (definitely HCC) were investigated, and imaging features were compared between IMCCs of LR-M and non-LR-M.

RESULTS

In all, 88.6% (31/35), 80.0% (28/35), and 74.3% (26/35) of IMCCs and 12.7% (9/71), 22.5% (16/71), and 16.9% (12/71) of HCCs were assigned as LR-M by the three reviewers with substantial interobserver agreements (kappa = 0.664-0.741). Among IMCCs, 2.9% (1/35), 5.7% (2/35), and 11.4% (4/35) were categorized as LR-5/5v. IMCCs of non-LR-M (n = 8, using the consensus method) were significantly smaller (24.1 ± 17.4 vs. 62.8 ± 30.6 mm, P = 0.002) and showed higher frequencies of arterial hyperenhancement (75.0% (6/8) vs. 7.4% (2/27), P < 0.001) and lower frequencies of non-HCC malignancy-favoring features such as peripheral enhancement (12.5% (1/8) vs. 77.8% (21/27), P = 0.002) or the target appearance on the hepatobiliary phase (0% (0/8) vs. 81.5% (22/27), P < 0.001) than IMCCs of LR-M (n = 27).

CONCLUSION

Using LI-RADS, the majority of IMCCs can be accurately categorized as LR-M on gadoxetic acid-enhanced MRI; however, caution is warranted, as some atypical IMCCs may be assigned as LR-5/5v resulting in a false-positive diagnosis of HCC. J. Magn. Reson. Imaging 2016;44:1330-1338.

Quality of Cancer Care in Patients with Cirrhosis and Hepatocellular Carcinoma

Hepatocellular carcinoma is the most common primary liver cancer in patients with cirrhosis and is the leading cause of mortality in these patients. Despite existence of robust clinical practice guidelines for surveillance, diagnosis, and management for hepatocellular carcinoma (HCC), the quality of care received by patients with HCC has been inconsistent. Several studies have reported disappointingly low surveillance rates in high-risk groups which likely contribute to most HCC cases being diagnosed at advanced stages. There is also data from large studies showing that significant under-referral to specialists and delay in initiation of treatment are linked to poor clinical outcomes. Given above circumstances, it is very important to perform studies which can identify areas in need of improvement in the care processes of HCC and design interventions to enhance quality of care. Unfortunately, data on validated quality indicators and quality metrics for HCC are non-existent. In this article, we review the existing literature pertaining to this issue and identify areas that need further research.

Hepatic imaging following intra-arterial embolotherapy

PURPOSE

To discuss guidelines and salient imaging findings of solid tumors treated with common intra-arterial procedures used in interventional oncology.

METHODS

A meticulous literature search of PubMed-indexed articles was conducted. Key words included "imaging + embolization," "imaging + TACE," "imaging + radioembolization," "imaging + Y90," "mRECIST," and "EASL." Representative post-treatment cross-sectional images were obtained from past cases in this institution.

RESULTS

Intra-arterial therapy (IAT) in interventional oncology includes bland embolization, chemoembolization, and radioembolization. Solid tumors of the liver are the primary focus of these procedures. Cross-sectional CT and/or MR are the main modalities used to image tumors after treatment. Traditional size-based response criteria (WHO and RECIST) alone are of limited utility in determining response to IAT; tumoral necrosis and enhancement must be considered. Specifically for HCC, the EASL and mRECIST guidelines are becoming widely adopted response criteria to assess these factors. DWI, FDG-PET, and CEUS are modalities that play an adjunctive but controversial role.

CONCLUSIONS

Radiologists must be aware that the different forms of intra-arterial therapy yield characteristic findings on cross-sectional imaging. Knowledge of these findings is integral to accurate assessment of tumor response and progression.

Evidence-Based Diagnosis, Staging, and Treatment of Patients With Hepatocellular Carcinoma

Evidence-based management of patients with hepatocellular carcinoma (HCC) is key to their optimal care. For individuals at risk for HCC, surveillance usually involves ultrasonography (there is controversy over use of biomarkers). A diagnosis of HCC is made based on findings from biopsy or imaging analyses. Molecular markers are not used in diagnosis or determination of prognosis and treatment for patients. The Barcelona Clinic Liver Cancer algorithm is the most widely used staging system. Patients with single liver tumors or as many as 3 nodules ≤3 cm are classified as having very early or early-stage cancer and benefit from resection, transplantation, or ablation. Those with a greater tumor burden, confined to the liver, and who are free of symptoms are considered to have intermediate-stage cancer and can benefit from chemoembolization if they still have preserved liver function. Those with symptoms of HCC and/or vascular invasion and/or extrahepatic cancer are considered to have advanced-stage cancer and could benefit from treatment with the kinase inhibitor sorafenib. Patients with end-stage HCC have advanced liver disease that is not suitable for transplantation and/or have intense symptoms. Studies now aim to identify molecular markers and imaging techniques that can detect patients with HCC at earlier stages and better predict their survival time and response to treatment.

A concise review of updated guidelines regarding the management of hepatocellular carcinoma around the world: 2010-2016

Many guidelines for hepatocellular carcinoma (HCC) have been published and updated globally. In contrast to other cancers, there is a range of treatment options for HCC involving several multidisciplinary care of the patient. Consequently, enormous heterogeneity in management trends has been observed. To support standard care for HCC, we systematically appraised 8 current guidelines for HCC around the world, including 3 guidelines from Asia, 2 from Europe, and 3 from the United States according to the selection criteria of credibility influence and multi-faceted. After a systematic appraisal, we found that these guidelines have both similarities and dissimilarities in terms of surveillance and treatment allocation recommendations due to regional differences in disease and other variables (diagnosis, staging systems) secondary to the lack of a solid, high level of evidence. In contrast to other tumors, the geographic differences in tumor biology (i.e., areas of increased hepatitis B prevalence) and available resources (organ availability for transplantation, medical technology, accessibility to treatment, health systems, and health resources) make it impractical to have an internationally universal guideline for all patients with HCC. Although Barcelona-Clinic Liver Cancer (BCLC) has long been dominant system for treatment-guiding staging of HCC, many Asia-pacific experts do not fully agree with its principle. The concepts of BCLC, for surgical resection or other locoregional therapy, are considered too conservative. Asian guidelines represent consensus about surgical resection and TACE indication for more advanced tumor.

Preliminary Outcome of Microwave Ablation of Hepatocellular Carcinoma: Breaking the 3-cm Barrier?

PURPOSE

To evaluate preliminary outcomes after microwave ablation (MWA) of hepatocellular carcinoma (HCC) up to 5 cm and to determine the influence of tumor size.

MATERIALS AND METHODS

Electronic records were searched for HCC and MWA. Between January 2011 and September 2014, 173 HCCs up to 5 cm were treated by MWA in 129 consecutive patients (89 men, 40 women; mean age, 66.9 y ± 9.5). Tumor characteristics related to local tumor progression and primary and secondary treatment efficacy were evaluated by univariate analysis. Outcomes were compared between tumors ≤ 3 cm and tumors > 3 cm.

RESULTS

Technical success, primary efficacy, and secondary efficacy were 96.5%, 99.4%, and 94.2% at a mean follow-up period of 11.8 months ± 9.8 (range, 0.8-40.6 mo). Analysis of tumor characteristics showed no significant risk factor for local tumor progression, including subcapsular location (P = .176), tumor size (P = .402), and perivascular tumor location (P = .323). The 1-year and 2-year secondary or overall treatment efficacy rates for tumors measuring ≤ 3 cm were 91.2% and 82.1% and for tumors 3.1-5 cm were 92.3% and 83.9% (P = .773). The number of sessions to achieve secondary efficacy was higher in the larger tumor group (1.13 vs 1.06, P = .005). There were three major complications in 134 procedures (2.2%).

CONCLUSIONS

With use of current-generation MWA devices, percutaneous ablation of HCCs up to 5 cm can be achieved with high efficacy.

Reassessing the boundaries of liver transplantation for hepatocellular carcinoma: Where do we stand with tumor down-staging?

Down-staging of hepatocellular carcinoma prior to liver transplantation (LT) has generated a lot of interest in recent years and has been identified in two recent national conferences on hepatocellular carcinoma as one of the priorities for research. Down-staging is defined as reduction in the tumor burden using local regional therapy specifically to meet acceptable criteria for LT. The rationale behind down-staging of tumors initially exceeding conventional criteria for LT is to select a subgroup of tumors with favorable biology and prognosis for LT as assessed by their response to local regional therapy. The expectation is to achieve comparable posttransplant survival between patients who achieve successful tumor down-staging before LT and those whose tumors meet LT criteria at the outset without needing down-staging. The application of tumor down-staging requires a highly structured approach using a treatment protocol that includes five essential components: eligibility criteria, down-staging endpoints, selection of the type of local regional therapy, minimal observation period from successful tumor down-staging to LT, and criteria for treatment failure and exclusion from LT. This review article summarizes published data on down-staging and addresses key questions related to each of the components of the down-staging protocol as well as treatment efficacy.

CONCLUSION

Based on a review of published data and recommendations from recent national and international conferences on hepatocellular carcinoma and LT, a standardized down-staging protocol is proposed to further evaluate the feasibility and efficacy of applying tumor down-staging on a broader scale.

Review of Commonly Used Serum Tumor Markers and Their Relevance for Image Interpretation

Serum tumor markers are firmly entrenched as one of the primary tools in an oncologist's armamentarium. They can be implemented in a broad range of applications from diagnostic assistance, assessing prognosis, or guiding therapeutic decisions. However, tumor markers also have limitations, which significantly impact how they should be used. Radiologists should be familiar with the following most prevalent tumor markers, which will all be discussed here: prostate-specific antigen (prostate), carcinoembryonic antigen (colon), α-fetoprotein (hepatocellular and testicular), carbohydrate antigen 19.9 (pancreas), cancer antigen 125 (ovarian), human chorionic gonadotropin/lactic dehydrogenase (testicular), and chromogranin A (neuroendocrine). This knowledge should avoid needless intervention, enhance image interpretation, and ultimately provide optimal patient care.

Does the Degree of Hepatocellular Carcinoma Tumor Necrosis following Transarterial Chemoembolization Impact Patient Survival?

Purpose. The association between transarterial chemoembolization- (TACE-) induced HCC tumor necrosis measured by the modified Response Evaluation Criteria In Solid Tumors (mRECIST) and patient survival is poorly defined. We hypothesize that survival will be superior in HCC patients with increased TACE-induced tumor necrosis. Materials and Methods. TACE interventions were retrospectively reviewed. Tumor response was quantified via dichotomized (responders and nonresponders) and the four defined mRECIST categories. Results. Median survival following TACE was significantly greater in responders compared to nonresponders (20.8 months versus 14.9 months, p = 0.011). Survival outcomes also significantly varied among the four mRECIST categories (p = 0.0003): complete, 21.4 months; partial, 20.8; stable, 16.8; and progressive, 7.73. Only progressive disease demonstrated significantly worse survival when compared to complete response. Multivariable analysis showed that progressive disease, increasing total tumor diameter, and non-Child-Pugh class A were independent predictors of post-TACE mortality. Conclusions. Both dichotomized (responders and nonresponders) and the four defined mRECIST responses to TACE in patients with HCC were predictive of survival. The main driver of the survival analysis was poor survival in the progressive disease group. Surprisingly, there was small nonsignificant survival benefit between complete, partial, and stable disease groups. These findings may inform HCC treatment decisions following first TACE.

Effect of MRI Versus MDCT on Milan Criteria Scores and Liver Transplantation Eligibility

OBJECTIVE

The Milan criteria for the selection of patients with hepatocellular carcinoma (HCC) for liver transplantation were originally based on the findings of contrast-enhanced CT examinations. Studies have shown improvement in HCC detection of using contrast-enhanced MRI instead of CT, but they have provided little information on the potential downstream effect on patient management that might result from discrepant imaging findings. We sought to assess the effect of discrepant imaging findings on patient eligibility to undergo liver transplantation.

MATERIALS AND METHODS

From 2006 to 2013, patients with a diagnosis of HCC who underwent both MDCT and MRI examinations within a 40-day period were studied retrospectively. All examinations were independently reviewed by two abdominal radiologists who recorded the number, diameter, and location of each lesion. Secondary confirmation of the lesions was made on the basis of histopathologic findings, diffusion restriction on DWI, increased T2 signal intensity, lesion growth, presence of fat, uptake of ethiodized oil, or a combination of these findings.

RESULTS

Sixty-four patients (48 men and 16 women; mean age, 62 years) met the criteria for inclusion in the study. Of the 129 lesions identified by MRI, only 102 of these lesions (79%) were identified by MDCT. This discrepancy led to a difference in the Milan criteria scoring for nine patients (14%). There was no statistically significant difference in the mean (± SD) greatest lesion diameter measured using the two modalities, with measurements of 3.52 ± 2.8 cm and 3.46 ± 2.8 cm noted on MDCT and MRI, respectively (p = 0.8). Lesions missed on MDCT studies tended to be smaller, with a mean diameter of 2.7 cm. Of the 129 lesions identified by MRI, 112 (87%) had available histopathologic findings or other confirmatory diagnostic evidence.

CONCLUSION

MDCT missed one-fifth of the HCC lesions detected by MRI. Had MDCT been the only imaging examination performed, failure to identify these lesions would have led to a different management plan for 14% of patients.

Magnetic resonance imaging of the cirrhotic liver in the era of gadoxetic acid

Gadoxetic acid improves detection and characterization of focal liver lesions in cirrhotic patients and can estimate liver function in patients undergoing liver resection. The purpose of this article is to describe the optimal gadoxetic acid study protocol for the liver, the unique characteristics of gadoxetic acid, the differences between gadoxetic acid and extra-cellular gadolium chelates, and the differences in phases of enhancement between cirrhotic and normal liver using gadoxetic acid. We also discuss how to obtain and recognize an adequate hepatobiliary phase.

Hypovascular hepatic nodules at gadoxetic acid-enhanced MRI: whole-lesion hepatobiliary phase histogram metrics for prediction of progression to arterial-enhancing hepatocellular carcinoma

PURPOSE

To explore whole-lesion histogram analysis of the hepatobiliary phase (HBP) defect in indeterminate hypovascular liver lesions for predicting progression to arterial-enhancing hepatocellular carcinoma (HCC).

METHODS

Twenty patients undergoing gadoxetic acid-enhanced MRI for HCC screening with 12° and 25° flip angle (FA) HBP acquisitions demonstrating an indeterminate lesion showing HBP hypointensity but no arterial enhancement were included. Volumes-of-interest were placed on HBP defects, from which histogram metrics were obtained. Associations between these metrics and progression to arterial-enhancing HCC on follow-up imaging were investigated. Lesions were also assessed for the presence of a signal abnormality on conventional sequences.

RESULTS

40% of lesions progressed to arterial-enhancing HCC; 60% were stable at ≥6 months follow-up. Neither T2-hyperintensity increased diffusion signal nor portal/equilibrium phase washout was different between progressing and nonprogressing lesions (p = 1.0). Among direct signal intensity-based measures (overall mean; mean of bottom 10th, 10-25th, and 25-50th percentiles), area-under-the-curve (AUC) for prediction of progression to arterial-enhancing HCC was consistently higher at 25° (range 0.619-0.657) than at 12° (range 0.512-0.548). However, at both FAs, the four measures with highest AUC were measures related to lesion texture and heterogeneity [standard deviation (SD), coefficient of variation (CV), skewness, and entropy], having AUC of 0.655-0.750 at 12° and 0.686-0.800 at 25. The metric with highest AUC at 12° was SD (AUC = 0.750) and at 25° was CV (AUC = 0.800).

CONCLUSION

Whole-lesion histogram HBP measures of indeterminate hypovascular liver lesions may help predict progression to arterial-enhancing HCC by reflecting greater lesion heterogeneity, particularly at higher FA. Larger studies are therefore warranted.

Noninvasive Diagnosis of Hepatocellular Carcinoma: Elaboration on Korean Liver Cancer Study Group-National Cancer Center Korea Practice Guidelines Compared with Other Guidelines and Remaining Issues

Hepatocellular carcinoma (HCC) can be diagnosed based on characteristic findings of arterial-phase enhancement and portal/delayed "washout" in cirrhotic patients. Several countries and major academic societies have proposed varying specific diagnostic criteria for HCC, largely reflecting the variable HCC prevalence in different regions and ethnic groups, as well as different practice patterns. In 2014, a new version of Korean practice guidelines for management of HCC was released by the Korean Liver Cancer Study Group (KLCSG) and the National Cancer Center (NCC). According to the KLCSG-NCC Korea practice guidelines, if the typical hallmark of HCC (i.e., hypervascularity in the arterial phase with washout in the portal or 3 min-delayed phases) is identified in a nodule ≥ 1 cm in diameter on either dynamic CT, dynamic MRI, or MRI using hepatocyte-specific contrast agent in high-risk groups, a diagnosis of HCC is established. In addition, the KLCSG-NCC Korea practice guidelines provide criteria to diagnose HCC for subcentimeter hepatic nodules according to imaging findings and tumor marker, which has not been addressed in other guidelines such as Association for the Study of Liver Diseases and European Association for the Study of the Liver. In this review, we briefly review the new HCC diagnostic criteria endorsed by the 2014 KLCSG-NCC Korea practice guidelines, in comparison with other recent guidelines; we furthermore address several remaining issues in noninvasive diagnosis of HCC, including prerequisite of sonographic demonstration of nodules, discrepancy between transitional phase and delayed phase, and implementation of ancillary features for HCC diagnosis.

Direct costs of care for hepatocellular carcinoma in patients with hepatitis C cirrhosis

BACKGROUND

Hepatitis C virus (HCV) is the commonest cause of hepatocellular carcinoma (HCC) in the United States. The benefits of HCV therapy may be measured in part by the prevention of HCC and other complications of cirrhosis. The true cost of care of the HCV patient with HCC is unknown.

METHODS

One hundred patients were randomly selected from a cohort of all HCC patients with HCV at a US transplant center between 2003 and 2013. Patients were categorized by the primary treatment modality, Barcelona class, and ultimate transplant status. Costs included the unit costs of procedures, imaging, hospitalizations, medications, and all subsequent care of the HCC patient until either death or the end of follow-up. Associations with survival and cost were assessed in multivariate regression models.

RESULTS

Overall costs included a median of $176,456 (interquartile range [IQR], $84,489-$292,192) per patient or $6279 (IQR, $4043-$9720) per patient-month of observation. The median costs per patient-month were $7492 (IQR, $5137-$11,057) for transplant patients and $4830 for nontransplant patients. The highest median monthly costs were for transplant patients with Barcelona A4 disease ($11,349) and patients who received chemoembolization whether they underwent transplantation ($10,244) or not ($8853). Transarterial chemoembolization and radiofrequency ablation were independently associated with a 28% increase and a 22% decrease in costs, respectively, with adjustments for the severity of liver disease and Barcelona class.

CONCLUSIONS

These data represent real-world estimates of the cost of HCC care provided at a transplant center and should inform economic studies of HCV therapy.

CT Appearance of Hepatocellular Carcinoma after Locoregional Treatments: A Comprehensive Review

Hepatocellular carcinoma (HCC) is a major health problem worldwide, affecting more than 600,000 new patients per year. Curative treatments are available in a small percentage of patients, while most of them present in stages requiring locoregional treatments such as thermoablation, transarterial chemoembolization, and/or radioembolization. These therapies result in specific imaging features that the general radiologist has to be aware of in order to assess the response to treatment and to correctly manage the follow-up of treated patients. Multiphasic helical computed tomography has become a popular imaging modality for detecting hypervascular tumors and characterizing liver lesions. On this basis, many staging and diagnostic systems have been proposed for evaluating response to all different existing strategies. Radiofrequencies and microwaves generate thermoablation of tumors, and transarterial chemoembolization exploits the double effect of the locoregional administration of drugs and embolizing particles. Eventually radioembolization uses a beta-emitting isotope to induce necrosis. Therefore, the aim of this comprehensive review is to analyze and compare CT imaging appearance of HCC after various locoregional treatments, with regard to specific indications for all possible procedures.

Computed Tomography Angiography of the Hepatic, Pancreatic, and Splenic Circulation

Multidetector computed tomography angiography (MDCTA) has become a routine imaging tool to assess visceral vascular anatomy and abdominal parenchymal pathology. Enhanced temporal resolution and rapid acquisition allow for precise delineation of arterial and venous anatomy. The excellent spatial resolution permits assessment of small parenchyma lesions and vasculature. The ability of CT to rapidly acquire data and reconstruct with thinner slices allows robust 3D mapping using maximum intensity projection before definitive surgical or interventional therapy. Emerging novel techniques of image acquisition offer sensitive methods for detecting enhancement and allow for virtual imaging subtraction, all while limiting the total radiation burden.

Diet-Induced Obesity Enhances Progression of Hepatocellular Carcinoma through Tenascin-C/Toll-Like Receptor 4 Signaling

Obesity is an independent risk factor for the development of liver fibrosis/cirrhosis and hepatocellular carcinoma (HCC). Tenascin-C (TnC), an extracellular matrix protein, is transiently expressed during tissue injury and plays a role in fibrogenesis and tumorigenesis. However, the mechanistic role of TnC signaling in the development of HCC remains unknown. We developed a diet-induced obesity HCC mouse model and examined TnC expression and liver injury. To determine the cellular mechanism of TnC signaling in promoting inflammation and hepatocyte epithelial-mesenchymal transition and migration, we used primary hepatocytes and hepatoma and macrophage cell lines. Further, to determine whether elevated TnC expression correlated with obesity-associated HCC, we measured plasma TnC in obese patients with various levels of liver injury. Increased tissue inflammation accompanied with elevated hepatic stellate cell-derived TnC and Toll-like receptor 4 expression was observed in the diet-induced obesity HCC animal model. In vitro studies found enhanced Toll-like receptor 4 signaling activated by TnC, promoting an increased inflammatory response, hepatocyte transformation, and migration. Further, obese patients with cirrhosis alone and in combination with HCC showed significant increases in plasma TnC compared with healthy volunteers and patients with less severe liver injury. Overall, these studies suggest TnC/Toll-like receptor 4 signaling as an important regulator in HCC; inhibiting this signaling axis may be a viable therapeutic target for impeding HCC.

Hepatocellular carcinoma: A comprehensive review

Hepatocellular carcinoma (HCC) is rapidly becoming one of the most prevalent cancers worldwide. With a rising rate, it is a prominent source of mortality. Patients with advanced fibrosis, predominantly cirrhosis and hepatitis B are predisposed to developing HCC. Individuals with chronic hepatitis B and C infections are most commonly afflicted. Different therapeutic options, including liver resection, transplantation, systemic and local therapy, must be tailored to each patient. Liver transplantation offers leading results to achieve a cure. The Milan criteria is acknowledged as the model to classify the individuals that meet requirements to undergo transplantation. Mean survival remains suboptimal because of long waiting times and limited donor organ resources. Recent debates involve expansion of these criteria to create options for patients with HCC to increase overall survival.

How reader perception of capsule affects interpretation of washout in hypervascular liver nodules in patients at risk for hepatocellular carcinoma

PURPOSE

To determine whether reader perception of a capsule affects reader interpretation of washout in hypervascular liver nodules at dynamic magnetic resonance imaging (MRI) in patients at risk for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

This retrospective study was Institutional Review Board (IRB)-approved and Health Insurance Portability and Accountability Act (HIPAA)-compliant, with waiver of informed consent. MRI reports for 111 hypervascular liver nodules (median 2.0 cm, range 1.0-17.8 cm) in 62 patients were reviewed, and the presence/absence of capsule and washout were recorded for one reading. A second independent study reading was also performed. The signal intensity ratio (SIR) for each nodule and liver parenchyma was measured. An objective SIR threshold was identified for nodules without capsules that correctly classified the presence/absence of washout, then applied to nodules with capsules to classify them as having / not having objective washout. Nodules were categorized as definite / not definite HCC using subjective and objective washout, based on LI-RADS, OPTN, AASLD, and EASL criteria, and proportions compared using McNemar's test.

RESULTS

Agreement on nodule features was high for Readings 1 and 2 (κ = 0.70-0.82). For Reading 1, 71 nodules lacked capsules (43 with and 28 without subjective washout); an SIR threshold of 0.88 classified the presence/absence of washout correctly in 94% (67/71, P < 0.001). Forty nodules had capsules; although all had subjective washout (100%, 40/40), 75% (30/40) had objective washout (P < 0.05). Using objective washout caused 4.5% (3/66; LI-RADS, OPTN) and 12% (10/83; AASLD, EASL) of nodules to be recategorized from definite HCC to not definite HCC.

CONCLUSION

Reader perception of capsule affects interpretation of washout. This effect can influence nodule categorization using imaging-based diagnostic systems. J. Magn. Reson. Imaging 2016;43:1337-1345.

Contrast Enhanced MRI in the Diagnosis of HCC

Hepatocellular carcinoma (HCC) is the 6th most common cancer worldwide. Imaging plays a critical role in HCC screening and diagnosis. Initial screening of patients at risk for HCC is performed with ultrasound. Confirmation of HCC can then be obtained by Computed Tomography (CT) or Magnetic Resonance Imaging (MRI), due to the relatively high specificity of both techniques. This article will focus on reviewing MRI techniques for imaging HCC, felt by many to be the exam of choice for HCC diagnosis. MRI relies heavily upon the use of gadolinium-based contrast agents and while primarily extracellular gadolinium-based contrast agents are used, there is an emerging role of hepatobiliary contrast agents in HCC imaging. The use of other non-contrast enhanced MRI techniques for assessing HCC will also be discussed and these MRI strategies will be reviewed in the context of the pathophysiology of HCC to help understand the MR imaging appearance of HCC.

Diagnosing Borderline Hepatic Nodules in Hepatocarcinogenesis: Imaging Performance

OBJECTIVE

The purposes of this article are to describe the pathologic and radiologic features of small nodular lesions and to offer insight into the multistep process of hepatocarcinogenesis by describing the progression of imaging changes that link dysplastic nodules and early hepatocellular carcinoma, (HCC) to small HCC that has progressed.

CONCLUSION

Nodules larger than 1 cm found during ultrasound surveillance of a cirrhotic liver should be investigated further with diagnostic imaging. Contrast-enhanced CT and dynamic MRI are the primary diagnostic studies for the diagnosis of HCC; contrast-enhanced ultrasound can be used as an alternative test. If a nodule has the typical hallmark of hypervascularity in the hepatic arterial phase with washout in the portal venous or delayed phase, a definitive diagnosis of HCC can be made. Nodules found during ultrasound surveillance that are smaller than 1 cm can be followed with ultrasound examinations at intervals of 3-6 months.