Impact of pretransplant diagnosis of hepatocellular carcinoma on cadveric liver allocation in the era of MELD

RESULTS OF IMMUNOHISTOCHEMISTRY IN THE DIFFERENTIAL DIAGNOSIS OF EARLY HEPATOCELLULAR CARCINOMA AND NODULES WITH HIGH-GRADE DYSPLASIA IN PATIENTS WITH CIRRHOSIS

BACKGROUND

Hepatocellular carcinoma (HCC) is the most frequent primary cancer of the liver and cirrhosis is considered a pre-malignant disease. In this context, the evolutionary sequence from low grade dysplastic nodule and high grade dysplastic nodule (HGDN) to early HCC and advanced HCC has been studied. The differential diagnosis between HGDN and early HCC is still a challenge, especially in needle biopsies.

OBJECTIVE

To evaluate an immunohistochemistry panel to differentiate dysplastic nodules and HCC.

METHODS

Patients with cirrhosis who underwent surgical resection or liver transplantation were included. The sensitivity, specificity and accuracy for the diagnosis of neoplasia were analyzed by evaluating five markers: heat shock protein 70, glypican 3, glutamine synthetase, clathrin heavy chain and beta-catenin. P≤0.05 was considered statistically significant.

RESULTS

One hundred and fifty-six nodules were included; of these, 57 were HCC, 14 HGDN, 18 low grade dysplastic nodules and 67 regenerative macronodules. Sensitivity of HCC diagnosis was 64.9% for glypican 3 and 77.2% for glutamine syntetase, while specificity was 96.0% and 96.0% respectively. When the panel of four markers was considered (excluding beta catenin), the specificity ranged from 87.9% for one positive marker to 100% for at least three markers. The best accuracy for HCC diagnosis was obtained with at least two positive markers, which was associated with a sensitivity of 82.5% and specificity of 99%.

CONCLUSION

Differential diagnosis of dysplastic nodules and HCC by morphological criteria can be challenging. Immunomarkers are useful and should be used for the differential diagnosis between HCC and HGDN.

LI-RADS and transplantation: challenges and controversies

Patients with early stage hepatocellular carcinoma (HCC) can be cured by liver transplantation. HCC imaging features on CT or MRI are specific enough to allow for definitive diagnosis and treatment without the need of confirmatory biopsy. When applied to the appropriate at-risk population the Liver Imaging Reporting and Data System (LI-RADS) imaging criteria achieve high specificity and positive predictive value for the diagnosis of HCC. The Organ Procurement and Transplantation Network (OPTN) is the United States organization that aims to assure the adequate and fair distribution of livers across candidates. Given the importance of fair organ allocation, OPTN also provides stringent imaging criteria for the diagnosis of HCC aiming to avoid false positive diagnosis. Although most imaging criteria are identical for both systems, discrepancies between LI-RADS and the current OPTN classification system for HCC diagnosis exists. Main differences include, but are not limited to, the binary approach of OPTN to classify lesions as HCC or not, versus the probabilistic algorithmic approach of LI-RADS, technical and interpretation considerations, and the approach towards treated lesions. The purpose of this article is to highlight the similarities and discrepancies between LI-RADS and the current OPTN criteria for HCC diagnosis and the implications that these differences may have on the management of patients who are transplant candidates.

Changing role of histopathology in the diagnosis and management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and fatal cancer in the world. HCC frequently presents with advanced disease, has a high recurrence rate and limited treatment options, which leads to very poor prognosis. This warrants urgent improvement in the diagnosis and treatment. Liver biopsy plays very important role in the diagnosis and prognosis of HCC, but with technical advancements and progression in the field of imaging, clinical guidelines have restricted the role of biopsy to very limited situations. Biopsy also has its own problems of needle tract seeding of tumor, small risk of complications, technical and sampling errors along with interpretative errors. Despite this, tissue analysis is often required because imaging is not always specific, limited expertise and lack of advanced imaging in many centers and limitations of imaging in the diagnosis of small, mixed and other variant forms of HCC. In addition, biopsy confirmation is often required for clinical trials of new drugs and targeted therapies. Tissue biomarkers along with certain morphological features, phenotypes and immune-phenotypes that serve as important prognostic and outcome predictors and as decisive factors for therapy decisions, add to the continuing role of histopathology. Advancements in cancer biology and development of molecular classification of HCC with clinic pathological correlation, lead to discovery of HCC phenotypic surrogates of prognostic and therapeutically significant molecular signatures. Thus tissue characteristics and morphology based correlates of molecular subtypes provide invaluable information for management and prognosis. This review thus focuses on the importance of histopathology and resurgence of role of biopsy in the diagnosis, management and prognostication of HCC.

Contemporary role of liver biopsy in hepatocellular carcinoma

A correct diagnosis of hepatocellular carcinoma (HCC) in cirrhotic patients with focal liver lesions is one of the most important issues nowadays. Probably one of the oldest debates in the hepatology community is whether to perform liver biopsy (LB) in all cirrhotic patients with focal liver lesions. We now face a time when oncology is moving towards personalized medicine. According to the current European Association for the study of Liver diseases HCC guidelines, LB has only a minor role in the management of HCC. However, the current recommendations were made more than five years ago. As time has passed, the development of high-throughput molecular technologies has helped reveal the main molecular mechanism involved in HCC development and progression. Several subtypes of HCC, with both molecular and histological characterization, have been described. Importantly, some of these subtypes have prognostic impact. In the context of personalized treatment, the role of LB will be carefully reconsidered. Until then, it is mandatory to know the various techniques of LB, their performances, complications and limitations. The balance of risk and benefit defines many of the decisions that we make as providers of medical care. In this review, we discuss not only the risks associated with LB, but also the benefits of biopsy in various clinical scenarios. Not long from now, the role of LB will be reconsidered. It is possible that we will go back in time and once again use biopsy for HCC diagnosis. Then again, we may move back to the future to try to improve the use of liquid biopsy in the follow-up of HCC patients after various treatment modalities.

LI-RADS and transplantation for hepatocellular carcinoma

Patients with hepatocellular carcinoma (HCC) may be eligible for liver transplantation. Liver transplant candidates with HCC compete for the same deceased donor organs as those without HCC. These scarce organs must be allocated fairly and justly to those who will benefit most. Unlike most other cancers, HCC is often diagnosed noninvasively by imaging without biopsy confirmation. Therefore, radiologists play an important role in diagnosing definite HCC (i.e., LR-5 category) that counts toward staging and determination of liver transplant eligibility. This review explains the conversion of LI-RADS observation categories to organ procurement and transplantation network classes, illustrates the radiologic T-staging systems, reviews selection criteria for liver transplant eligibility, and discusses prioritization of liver transplant candidates with HCC. In addition, this review summarizes imaging requirements, including contrast agents accepted, minimum specifications for dynamic CT or MRI of the liver, and modalities accepted for assessment of extrahepatic spread or metastatic disease in liver transplant candidates with HCC.

Hepatocellular carcinoma imaging systems: why they exist, how they have evolved, and how they differ

Over the past 16 years, several scientific organizations have proposed systems that incorporate imaging for surveillance, diagnosis, staging, treatment, and monitoring of treatment response of hepatocellular carcinoma (HCC). These systems are needed to standardize the acquisition, interpretation, and reporting of liver imaging examinations; help differentiate benign from malignant observations; improve consistency between radiologists; and provide guidance for management of HCC. This review article discusses the historical evolution of HCC imaging systems. We indicate the features differentiating these systems, including target population, screening and surveillance algorithm, diagnostic imaging modalities, diagnostic scope, expertise and technical requirements, terminology, major and ancillary imaging features, staging and transplant eligibility, and assessment of treatment response. We highlight the potential benefits of unifying the systems, which we anticipate will enable sharing, pooling, and meta-analysis of data; facilitate multi-center trials; and accelerate dissemination of knowledge.

Misdiagnosis of hepatocellular carcinoma in patients receiving no local-regional therapy prior to liver transplant: An analysis of the Organ Procurement and Transplantation Network explant pathology form

Patients with T1 hepatocellular carcinoma (HCC) are not eligible for Model for End Stage Liver Disease (MELD) exception for liver transplant (LT) in part due to a high rate of misdiagnosis (no HCC on explant). The likelihood of misdiagnosis for T2 HCC and factors associated with misdiagnosis are unknown. We analyzed the Organ Procurement and Transplantation Network database including 5664 adults who underwent LT from 2012 to 2015 with MELD exception for T2 HCC, and searched for no evidence of HCC in the explant pathology file. We focused on those (n = 324) receiving no local-regional therapy (LRT) to evaluate the probability of no HCC found in explant. Median waiting time was short at 1.7 months, and 35 (11%) had no HCC on explant. On multivariable logistic regression, factors associated with no HCC on explant were age <50 (OR: 17.3, P < .001), non-HCV (OR: 5.4, P = .001), and alpha-fetoprotein <10 (OR: 2.9, P = .04). Tumor size and number were not different between groups. The proportion of misdiagnosis did not change significantly after implementation of Liver Imaging Reporting and Data System (LI-RADS) for HCC diagnosis.

CONCLUSION

The rate of misdiagnosis was 11% among T2 HCC patients who underwent LT without receiving LRT prior to LT and did not change significantly after implementation of LI-RADS. More efforts are needed to eliminate unnecessary LT for patients without HCC.

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.

Prediction of hepatocellular carcinoma biological behavior in patient selection for liver transplantation

Morphological criteria have always been considered the benchmark for selecting hepatocellular carcinoma (HCC) patients for liver transplantation (LT). These criteria, which are often inappropriate to express the tumor’s biological behavior and aggressiveness, offer only a static view of the disease burden and are frequently unable to correctly stratify the tumor recurrence risk after LT. Alpha-fetoprotein (AFP) and its progression as well as AFP-mRNA, AFP-L3%, des-γ-carboxyprothrombin, inflammatory markers and other serological tests appear to be correlated with post-transplant outcomes. Several other markers for patient selection including functional imaging studies such as ¹⁸F-FDG-PET imaging, histological evaluation of tumor grade, tissue-specific biomarkers, and molecular signatures have been outlined in the literature. HCC growth rate and response to pre-transplant therapies can further contribute to the transplant evaluation process of HCC patients. While AFP, its progression, and HCC response to pre-transplant therapy have already been used as a part of an integrated prognostic model for selecting patients, the utility of other markers in the transplant setting is still under investigation. This article intends to review the data in the literature concerning predictors that could be included in an integrated LT selection model and to evaluate the importance of biological aggressiveness in the evaluation process of these patients.

Comparative 13-year meta-analysis of the sensitivity and positive predictive value of ultrasound, CT, and MRI for detecting hepatocellular carcinoma

PURPOSE

To compare the per-lesion sensitivity and positive predictive value (PPV) of ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) for the diagnosis of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

The meta-analysis of sensitivity included 242 studies (15,713 patients); 116 studies (7492 patients) allowed calculation of PPV. Pooled per-lesion sensitivity and PPV for HCC detection were compared using empirical Bayes estimates of a beta-binomial model.

RESULTS

The pooled per-lesion sensitivity and PPV of contrast-enhanced CT (73.6%, 85.8%) and gadolinium-enhanced MRI (77.5%, 83.6%) are not significantly different (P = 0.08, P = 0.2). However, if the hepatobiliary agent gadoxetate is used, MRI has significantly higher pooled per-lesion sensitivity and PPV (85.6%, 94.2%) than CT (P < 0.0001) or than MRI with other agents (P < 0.0001). Non-contrast-enhanced US has the lowest overall sensitivity and PPV (59.3%, 77.4%). Pooled per-lesion sensitivity and PPV of contrast-enhanced US (84.4%, 89.3%) are relatively high, but no contrast-enhanced US study used the most rigorous reference standards.

CONCLUSION

MRI utilizing the hepatobiliary agent gadoxetate has the highest overall sensitivity and PPV, and may be the single optimal method for diagnosis of HCC. Non-contrast-enhanced US has the lowest sensitivity and PPV. More rigorous reference standards are needed to compare the performance of contrast-enhanced US with CT and MRI. Differences in sensitivity and PPV between CT and conventional gadolinium-enhanced MRI are not statistically significant overall.

Liver transplantation as a management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and has a poor prognosis if untreated. It is ranked the third among the causes of cancer-related death. There are multiple etiologic factors that can lead to HCC. Screening for early HCC is challenging due to the lack of well specific biomarkers. However, early diagnosis through successful screening is very important to provide cure rate. Liver transplantation (LT) did not gain wide acceptance until the mid-1980s, after the effective immunosuppression with cyclosporine became available. Orthotopic LT is the best therapeutic option for early, unresectable HCC. It is limited by both, graft shortage and the need for appropriate patient selection. It provides both, the removal of tumor and the remaining cirrhotic liver. In Milan, a prospective cohort study defined restrictive selection criteria known as Milan criteria (MC) that led to superior survival for transplant patients in comparison with any other previous experience with transplantation or other options for HCC. When transplantation occurs within the established MC, the outcomes are similar to those for nonmalignant liver disease after transplantation. The shortage of organs from deceased donors has led to the problems of long waiting times and dropouts. This has led to the adoption of extended criteria by many centers. Several measures have been taken to solve these problems including prioritization of patients with HCC, use of pretransplant adjuvant treatment, and living donor LT.

Role of FNAC in Hepatic lesions: Risk of track metastases

Background:

Liver is one of the most common site of metastases in patients with malignancy and the evaluation of space occupying lesions (SOL) of liver in patients with malignancy is important. Its important to differentiate benign from malignant to take necessary decisions.

Materials and Methods:

We have performed a retrospective analysis of liver SOLs for which fine needle aspiration cytology (FNAC) was done in the year 2011. Risks and benefits associated with FNAC were evaluated.

Results:

We analyzed 755 patients who underwent FNAC of which 524 patients had secondary metastases to liver, 148 patients had primary hepatocellular carcinoma, 14 cases were benign neoplasms and 53 were nonneoplastic conditions. Histological correlation with FNAC was available in 112 patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 93%, 90.9%, 98.9%, 58.8%, and 92.8%, respectively. Though there were no incidence of bleeding, two patients developed track metastases following FNAC. One was a case of Hepatocellular carcinoma and the other a case of metastatic breast cancer.

Conclusion:

FNAC was very much useful in our setup where most of the patients could not afford for Computer tomography (CT) scan and was useful in counseling them especially in patients with advanced malignancy where no active cancer directed therapy is required.

Evaluating the validity of model for end-stage liver disease exception points for hepatocellular carcinoma patients with multiple nodules <2 cm

Liver transplant allocation policy does not give model for end-stage liver disease (MELD) exception points for patients with a single hepatocellular carcinoma (HCC) <2 cm in size, but does give points to patients with multiple small nodules. Because standard-of-care imaging for HCC struggles to differentiate HCC from other nodules, it is possible that a subset of patients receiving liver transplant for multiple nodules <2 cm in size does not have HCC. We evaluate risk of post-transplant HCC recurrence and wait-list dropout for patients with multiple small nodules using competing risks regression based on the Fine and Gray model. We identified 5002 adult HCC patients in the OPTN/UNOS dataset diagnosed and transplanted between January 2006 and September 2010. Compared to patients with >1 tumor <2 cm, risk of developing recurrence was significantly higher in patients with one or more tumors with only one tumor ≥2 cm (SHR 1.63, p = 0.009), as well as in patients with 2-3 tumors ≥2 cm (SHR 1.84, p = 0.02). Dropout risk was not significantly different among size categories. HCC recurrence risk was significantly lower in patients with multiple nodules <2 cm in size than in those with larger tumors, supporting the possibility that some patients received unnecessary transplants. The priority given to these patients must be re-examined.

Waiting time predicts survival after liver transplantation for hepatocellular carcinoma: a cohort study using the United Network for Organ Sharing registry

Recipients of liver transplantation (LT) for hepatocellular carcinoma (HCC) have an 8% to 20% risk of HCC recurrence. Single-center studies suggest that a period of waiting after HCC therapy may facilitate the selection of patients at low risk for post-LT HCC recurrence and mortality. We evaluated whether a longer waiting time after Model for End-Stage Liver Disease (MELD) prioritization for HCC predicts longer post-LT survival. From the United Network for Organ Sharing registry, we selected 2 groups registered for LT between March 2005 and March 2009: (1) HCC patients receiving MELD prioritization and (2) non-HCC patients. Patients were stratified by their MELD status at LT (a marker of time on the wait list after HCC MELD prioritization) and were followed from LT until death or censoring through October 2012. By comparing post-LT survival to intention-to-treat (ITT) survival from registration, we assessed predictors of post-LT survival and estimated the benefit of LT. The median MELD scores at LT were 22 (HCC) and 24 (non-HCC). A higher MELD score at LT was independently associated with lower post-LT mortality in the HCC group [hazard ratio (HR) = 0.84, 95% confidence interval (CI) = 0.73-0.98] and higher post-LT mortality in the non-HCC group (HR = 1.20, 95% CI = 1.15-1.25). Compared with the HCC group, the non-HCC group had lower post-LT mortality [relative risk (RR) = 0.85, log-rank P < 0.01] but higher ITT mortality (RR = 1.25, log-rank P < 0.01) because of a 33 percentage point lower probability of undergoing LT. In conclusion, a longer waiting time before LT for HCC predicted longer post-LT survival in a national transplant registry. Delaying LT for HCC may reduce disparities in ITT survival and access to LT among different indications and thereby improve system utility and organ allocation equity for the overall pool of LT candidates.

ACG clinical guideline: the diagnosis and management of focal liver lesions

Focal liver lesions (FLL) have been a common reason for consultation faced by gastroenterologists and hepatologists. The increasing and widespread use of imaging studies has led to an increase in detection of incidental FLL. It is important to consider not only malignant liver lesions, but also benign solid and cystic liver lesions such as hemangioma, focal nodular hyperplasia, hepatocellular adenoma, and hepatic cysts, in the differential diagnosis. In this ACG practice guideline, the authors provide an evidence-based approach to the diagnosis and management of FLL.

Post liver transplant presentation of needle-track metastasis of hepatocellular carcinoma following percutaneous liver biopsy

Hepatocellular carcinoma (HCC) is one of the few malignant tumours often treated without prior histological confirmation (in the patient with cirrhosis). Contrast-enhanced cross-sectional imaging is frequently diagnostic of HCC with a high degree of accuracy. However, on occasion, a liver biopsy is required, a complication of which can be needle-track metastasis. We present the case of a 57-year-old man who had previously undergone a liver transplant; he was found to have abdominal wall metastasis at the site of a prior percutaneous biopsy. This is the second case until now date of needle-track metastasis that presented following liver transplantation.

Glypican-3-targeted 89Zr PET imaging of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a devastating malignancy in which imperfect imaging plays a primary role in diagnosis. Glypican-3 (GPC3) is an HCC-specific cell surface proteoglycan overexpressed in most HCCs. This paper presents the use of (89)Zr-conjugated monoclonal antibody against GPC3 ((89)Zr-αGPC3) for intrahepatic tumor localization using PET.

METHODS

Polymerase chain reaction confirmed relative GPC3 expression in cell lines. In vitro binding, in vivo biodistribution, and small-animal PET studies were performed on GPC3-expressing HepG2 and non-GPC3-expressing HLF and RH7777 cells and orthotopic xenografts.

RESULTS

(89)Zr-αGPC3 demonstrated antibody-dependent, antigen-specific tumor binding. HepG2 liver tumors exhibited high peak uptake (836.6 ± 86.6 percentage injected dose [%ID]/g) compared with background liver (27.5 ± 1.6 %ID/g). Tumor-to-liver contrast ratio was high and peaked at 32.5. The smallest HepG2 tumor (<1 mm) showed lower peak uptake (42.5 ± 6.4 %ID/g) and tumor-to-liver contrast (1.57) but was still clearly visible on PET. Day 7 tissue activity was still substantial in HepG2 tumors (466.4 ± 87.6 %ID/g) compared with control RH7777 tumors (3.9 ± 1.3 %ID/g, P < 0.01), indicating antigen specificity by (89)Zr-αGPC3. HepG2 tumor treated with unlabeled αGPC3 or heat-denatured (89)Zr-αGPC3 demonstrated tumor activity (2.1 %ID/g) comparable to that of control xenografts, confirming antibody dependency.

CONCLUSION

This study demonstrated the feasibility of using (89)Zr-αGPC3 to image HCC in the liver, as well as the qualitative determination of GPC3 expression via small-animal PET. The ability to clarify the identity of small liver lesions with an HCC-specific PET probe would provide clinicians with vital information that could significantly alter patient management, warranting further investigation for clinical translation.

Validation of organ procurement and transplant network (OPTN)/united network for organ sharing (UNOS) criteria for imaging diagnosis of hepatocellular carcinoma

BACKGROUND

Imaging diagnosis of hepatocellular carcinoma (HCC) presents an important pathway for transplant exception points and priority for cirrhotic patients. The purpose of this retrospective study is to evaluate the validity of the new Organ Procurement and Transplant Network (OPTN) classification system on patients undergoing transplantation for HCC.

METHODS

One hundred twenty-nine patients underwent transplantation for HCC from April 14, 2006 to April 18, 2011; a total of 263 lesions were reported as suspicious for HCC on pretransplantation magnetic resonance imaging. Magnetic resonance imaging examinations were reviewed independently by two experienced radiologists, blinded to final pathology. Reviewers identified major imaging features and an OPTN classification was assigned to each lesion. Final proof of diagnosis was pathology on explant or necrosis along with imaging findings of ablation after transarterial chemoembolization.

RESULTS

Application of OPTN imaging criteria in our population resulted in high specificity for the diagnosis of HCC. Sensitivity in diagnosis of small lesions (≥1 and <2 cm) was low (range, 26%-34%). Use of the OPTN system would have resulted in different management in 17% of our population who had received automatic exception points for HCC based on preoperative imaging but would not have met criteria under the new system. Eleven percent of the patients not meeting OPTN criteria were found to have T2 stage tumor burden on pathology.

CONCLUSIONS

The OPTN imaging policy introduces a high level of specificity for HCC but may decrease sensitivity for small lesions. Management may be impacted in a number of patients, potentially requiring longer surveillance periods or biopsy to confirm diagnosis.

Clinical impact of an adaptive statistical iterative reconstruction algorithm for detection of hypervascular liver tumours using a low tube voltage, high tube current MDCT technique

OBJECTIVES

To investigate the impact of an adaptive statistical iterative reconstruction (ASiR) algorithm on diagnostic accuracy and confidence for the diagnosis of hypervascular liver tumours, as well as the reader's perception of image quality, using a low tube voltage (80 kVp), high tube current computed tomography (CT) technique.

METHODS

Forty patients (29 men, 11 women) with 65 hypervascular liver tumours underwent dual energy CT. The 80 kV set of the dual energy acquisition was reconstructed with standard filtered backprojection (FBP) and ASiR at different blending levels. Lesion contrast-to-noise ratio (CNR), reader's confidence for lesion detection and characterisation, and reader's evaluation of image quality were recorded.

RESULTS

ASiR yielded significantly higher CNR values compared with FBP (P < 0.0001 for all comparisons). Reader's perception of lesion conspicuity and confidence in the diagnosis of malignancy were also higher with 60 % and 80 % ASiR, compared with FBP (P = 0.01 and < 0.001, respectively). Compared with FBP, ASiR yielded nearly significantly lower specificity for lesion detection and a substantial decrease in the reader's perception of image quality.

CONCLUSIONS

Compared with the standard FBP algorithm, ASiR significantly improves conspicuity of hypervascular liver lesions. This improvement may come at the cost of decreased specificity and reader's perception of image quality.

Developments in liver transplantation for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a serious health problem worldwide because of its association with hepatitis B and C viruses. In this setting, liver transplantation (LT) has become one of the best treatments since it removes both the tumor and the underlying liver disease. Due to the improvement of imaging techniques and surveillance programs, HCC are being detected earlier at a stage at which effective treatment is feasible. The prerequisite for long term success of LT for HCC depends on tumor load and strict selection criteria with regard to the size and number of tumor nodules. The need to obtain the optimal benefit from the limited number of organs available has prompted the maintenance of selection criteria in order to list only those patients with early HCC who have a better long-term outcome after LT. The indications for LT and organ allocation system led to many controversies around the use of LT in HCC patients. This review aims at giving the latest updated developments in LT for HCC focusing on selection criteria, diagnostic tools, prognostic factors, treatment on the waiting list, role of living donor liver transplantation and adjuvant therapy, and the impact of immunosuppression on HCC recurrence after LT.

Anatomic pathology of hepatocellular carcinoma: impact on prognosis and response to therapy

A better understanding of signaling pathways in HCC pathogenesis has led to targeted therapies against HCC. Identification of liver cancer stem cell markers and their related pathways is one of the most important goals of liver cancer research. New therapies should ideally target cancer stem cells and not normal stem/progenitor cells, because the latter are very important in regeneration and repair. Individualized HCC therapy will require better definition of patient subgroups that benefit most or should be protected from therapy failure and unwanted side effects. Tumor tissue acquisition should be mandatory, reversing the practice that was established years ago when targeted HCC therapy was but a pipe dream.

Diagnostic imaging and biopsy use among elderly medicare beneficiaries with hepatocellular carcinoma

PURPOSE

Diagnostic imaging is effective for evaluating patients suspected of having hepatocellular carcinoma (HCC). Although the diagnosis can be established with imaging alone, diagnostic biopsy may be useful for patients with tumors measuring 1 to 2 cm. To date, biopsy and imaging use among patients with HCC has not been evaluated in the general community.

PATIENTS AND METHODS

This cohort study used Surveillance, Epidemiology, and End Results (SEER) -Medicare data (2002-2005) evaluating biopsy, imaging modalities (ultrasound, computed tomography [CT] scan, and/or magnetic resonance imaging [MRI]), and HCC risk factors.

RESULTS

Of 3,696 patients, 1,197 (32.4%) underwent one or more biopsies, with no change in yearly biopsy rate (trend test, P = .64). Patients with tumors > 5 cm were most likely to receive biopsies (35.3%), with increasing rates of biopsy for larger tumors (P = .001). Patients who received biopsies underwent more imaging than those who did not (P < .001) and were more likely to have an HCC risk factor. Tumor size > 5 cm in the setting of a concurrent HCC risk factor increased the odds of biopsy. In 47.8% of patients, the diagnostic sequence was not consistent with contemporary evidence-based guidelines.

CONCLUSIONS

Despite widespread availability and use of CT scan and MRI, one third of HCC patients undergo biopsy, suggesting a problem with the performance and/or quality of diagnostic imaging or that providers do not believe imaging alone is sufficient to establish the diagnosis. Understanding factors that drive biopsy use may help improve the care of patients with HCC.

Outcomes of loco-regional therapy for down-staging of hepatocellular carcinoma prior to liver transplantation

BACKGROUND

The number of loco-regional therapies (LRTs) for hepatocellular carcinoma (HCC) has increased dramatically during the past decade. Many patients with HCC who were beyond the Milan criteria were allowed to receive a liver transplantation (LT) once the HCC was successfully down-staged. This retrospective study aimed to analyze the outcomes of LRTs prior to LT in patients with HCC beyond the Milan criteria.

METHODS

We analyzed 56 patients treated from June 2006 to March 2010: 22 met the Milan criteria (T1+T2, 39.3%), 16 had T3 tumors (28.6%), and 11 had T4a tumors (19.6%), while 7 were suspected of tumor vascular invasion (T4b, 12.5%). All patients underwent preoperative LRTs, including transcatheter arterial chemoembolization, radiofrequency ablation, percutaneous ethanol injection, liver resection, and/or microwave coagulation therapy. The number of the patients who were successfully down-staged before LT, the types of LRTs used before LT, and their outcomes after LT were recorded.

RESULTS

Eleven patients had necrotic tumors (pT0, 19.6%); 6 had pT1 tumors (10.7%), 22 had pT2 tumors (39.3%), 6 had pT3 tumors (10.7%), 5 had pT4a tumors (8.9%), and 6 had pT4b tumors (10.7%). The histopathologic tumors of 39 patients (69.6%) were down-staged and met the established Milan criteria (pT0-2). Imaging-proven under-staging was present in 5 HCC patients (8.9%) who had tumors involving the intrahepatic venous system. Twenty-three patients (41.1%) had stable HCC and 10 (17.9%) died. The 1-, 3- and 4-year survival rates were 96%, 73% and 61%, respectively, with a mean survival time of 22.29+/-1.63 months. Six patients died of tumor recurrence. The 1-, 3- and 4-year recurrence-free survival (RFS) rates were 88%, 75% and 66%, respectively. The 3-year RFS of patients with pT0-2 tumors was 82%, which was markedly greater than that of patients with pT3 tumors (63%, P=0.018) or pT4 tumors (17%, P=0.000). Although the 3-year RFS of patients with pT3 tumors was greater than that of patients with pT4 tumors, the difference was not significant.

CONCLUSIONS

Successful down-staging of HCCs can be achieved in the majority of carefully selected patients by LRTs. Importantly, patients who are successfully down-staged and undergo LT may have a higher RFS rate.

Value of delayed hypointensity and delayed enhancing rim in magnetic resonance imaging diagnosis of small hepatocellular carcinoma in the cirrhotic liver

PURPOSE

To determine the diagnostic utility of delayed hypointensity and delayed enhancing rim on magnetic resonance imaging (MRI) as indicators of hepatocellular carcinoma (HCC) in arterially enhancing nodules < or =5 cm in the cirrhotic liver and determine the features that best predict HCC.

MATERIALS AND METHODS

Gadolinium-enhanced MRI studies performed from January 2001 to December 2004 in patients with cirrhosis were evaluated for arterially enhancing nodules measuring < or =5 cm. Verification was via explant correlation, biopsy, or imaging follow-up. Sensitivity and specificity of diagnostic features of HCC were calculated. Features predictive of HCC were determined using the Generalized Estimating Equation approach.

RESULTS

In all, 116 arterially enhancing nodules were identified in 80 patients (<2 cm: n = 79, 2-5 cm n = 37). Sensitivity and specificity of delayed hypointensity for HCC measuring < or =5 cm, 2-5 cm, and <2 cm were 0.54 (40 of 74) and 0.86 (36 of 42); 0.72 (23 of 32) and 0.80 (4 of 5); and 0.41 (17 of 42) and 0.87 (32 of 37). For the delayed enhancing rim sensitivity and specificity were 0.64 (47 of 74) and 0.86 (36 of 42); 0.75 (24 of 32) and 1.0 (5 of 5); and 0.55 (23 of 42) and 0.83 (31 of 37), respectively. Lesion size (> or =2 cm) and delayed enhancing rim, as main features and their interaction, were the most significant predictors of HCC.

CONCLUSION

Delayed hypointensity and enhancing rim improve the specificity of diagnosis of HCC of all sizes but are seen less frequently in small (<2 cm) HCC. Nodule size (> or =2 cm) and delayed enhancing rim are the strongest predictors of HCC.

Contrast-enhanced 3D ultrasonography in minute hepatocellular carcinoma

PURPOSE

The study aimed to clarify whether contrast-enhanced (CE) three-dimensional (3D) ultrasonography (US) can depict characteristic hyperstain and washout patterns in minute nodules ≤10 mm of hepatocellular carcinoma (minute HCC), and whether it serves as a potent diagnostic modality.

METHODS

CE 3D US was carried out to depict hyperstain and washout of a solitary nodule ≤10 mm in patients with liver cirrhosis. When both patterns were depicted with success, CE computed tomography (CT) and CE magnetic resonance imaging (MRI) were also carried out as part of a comparative study, and then a histological specimen was obtained by needle biopsy. The final diagnosis was based on the histopathological findings and a follow-up on the growth of nodules.

RESULTS

All 12 minute nodules exhibiting hyperstain and washout showed evidence of HCC when examined by CE 3D US. The CE CT and CE MRI examinations could depict both of these patterns, characteristic of HCC, in most of the nodules but rather less successfully than CE 3D US.

CONCLUSION

CE 3D US can depict hyperstain and washout patterns in minute HCC and serves as a potent modality for diagnosis.

Hepatocellular carcinoma: consensus recommendations of the National Cancer Institute Clinical Trials Planning Meeting

Hepatocelluar carcinoma (HCC) is the most common primary malignancy of the liver in adults and the third most common cause of cancer death worldwide. The incidence of HCC in the United States is rising steadily because of the prevalence of hepatitis C viral infection and other causes of hepatic cirrhosis. The majority of patients have underlying hepatic dysfunction, which complicates patient management and the search for safe and effective therapies. The Clinical Trials Planning Meeting (CTPM) in HCC was convened by the National Cancer Institute's Gastrointestinal Cancer Steering Committee to identify the key knowledge gaps in HCC and define clinical research priorities. The CTPM structured its review according to current evidence-based treatment modalities in HCC and prioritized the recommendations on the basis of the patient populations representing the greatest unmet medical need.

Current controversies surrounding liver transplantation for hepatocellular carcinoma

Liver transplantation (LT) for hepatocellular carcinoma (HCC) has progressed rapidly over the last decade from a futile therapy to the first choice therapy for suitable patients. Excellent outcomes of LT for HCC can be largely attributed to the use of the Milan Criteria, which have restricted LT to patients with early stage tumors. These criteria may be conservative, and it is likely that a subset of patients with tumors beyond these criteria can have acceptable outcomes. However, there is currently insufficient data to accept more liberal criteria as a standard of care, and a higher quality evidence base must be achieved to prevent poor utilization of valuable donor liver resources. In the future, it is probable that more sophisticated selection criteria will emerge incorporating aspects of tumor biology beyond tumor size and number. Dropout from the waiting list due to tumor progression remains a clinical challenge particularly in regions with prolonged waiting times. Priority allocation using HCC MELD points is a practical and transparent solution that has successfully reduced waitlist dropout for HCC patients. Further refinements of the HCC MELD point system are required to ensure equity of access to LT for non-HCC patients and prioritization of HCC patients with the highest risk of dropout. Improving the evidence base for pre-LT locoregional therapy to prevent waitlist dropout is an urgent and difficult challenge for the LT community. In the interim transplant clinicians must restrict the use of these therapies to those patients who are most likely to benefit from them.

Survival after liver transplantation for hepatocellular carcinoma in the model for end-stage liver disease and pre-model for end-stage liver disease eras and the independent impact of hepatitis C virus

It has been suggested that hepatitis C virus (HCV) patients with hepatocellular carcinoma (HCC) may have worse outcomes after liver transplantation (LT) because of more aggressive tumor biology. In this study, we determined the post-LT survival of HCC patients with and without HCV using United Network for Organ Sharing data from January 1994 to March 2008. Patients with HCC were stratified into HCV (HCC-HCV) and non-HCV (HCC-non-HCV) groups. In the era before the Model for End-Stage Liver Disease (MELD), there were 1237 HCC patients (780, HCV; 373, non-HCV; 84, unknown HCV status), and during the MELD era, there were 4933 HCC patients (3272, HCV; 1348, non-HCV; 313, unknown). In the pre-MELD era, 5-year graft (58.6% versus 53.7%) and patient (61.7% versus 59.3%) survival rates were marginally higher for HCC-non-HCV patients than for HCC-HCV patients. In the MELD era also, 5-year graft (61.2% versus 55.5%) and patient (63.7% versus 58.2%) survival rates were marginally higher for HCC-non-HCV patients than for HCC-HCV patients. In patients without HCC, pre-MELD and MELD era graft/patient survival rates for non-HCV patients were higher than those for HCV patients. The differences in survival rates for HCC patients with and without HCV were lower than those for non-HCC patients stratified by their HCV status. HCV had no additional negative impact on the post-LT survival of patients with HCC, and this was further confirmed by multivariate analysis. In conclusion, the survival of HCC patients has remained unchanged in the past 2 decades. HCV patients have a lower survival rate than non-HCV patients, regardless of their HCC status, but HCV has no additional negative impact on survival in patients with HCC.

Liver transplantation for hepatocellular carcinoma without preoperative tumor biopsy

BACKGROUND

Progress in liver imaging has made pretransplantation tumor biopsy no longer systematic in patients with hepatocellular carcinoma (HCC).

OBJECTIVES

Our aim was to evaluate the accuracy of a preoperative diagnosis of HCC based on clinical and radiological findings in 102 cirrhotics qualified for liver transplantation (LT) between January 1995 and August 2003 at our institution.

METHODS

The diagnostic accuracy of our policy was assessed by comparing pretransplant diagnosis with the pathologic report of explanted livers.

RESULTS

Sensitivity, specificity, positive, and negative predictive values for the preoperative clinical and radiological diagnosis of HCC were 89%, 94.3%, 77%, and 93.3%, respectively. A false-positive preoperative diagnosis was made in 20 of 102 patients (19.6%) (dysplastic nodules [n=9], regenerative nodules [n=5] cholangiocellular carcinoma [n=1], hemangioma [n=1], and no lesion [n=4]). All tumors larger than 3 cm were correctly diagnosed, irrespective of serum alpha-fetoprotein (sAFP) levels. The risk of overestimating the diagnosis of HCC in the subgroup of patients with tumors less than 3 cm was conversely correlated with preliver transplantation sAFP (sAFP<or=100 ng/L: 28%; sAFP>100: 11%; sAFP>200: 0%).

CONCLUSION

In cirrhotics with nodules larger than 3 cm irrespective of sAFP or nodules less than 3 cm with sAFP greater than 200 ng/L, the pretransplant diagnosis of HCC can be made without performing biopsy. In other cases (i.e., nodules less than 3 cm and sAFP lower than 200 ng/L), histologic confirmation of HCC or a close follow-up imaging should be considered.

Current approach to down-staging of hepatocellular carcinoma prior to liver transplantation

PURPOSE OF REVIEW

Orthotopic liver transplantation is currently the best curative treatment for hepatocellular carcinoma within conventional Milan criteria. Recent data have suggested that modest expansion of tumor size limits could still preserve acceptable long-term recurrence-free survival. Down-staging of hepatocellular carcinoma initially exceeding conventional criteria for transplantation provides a unique perspective on tumor biology in that those with more favorable tumor biology are more likely to be successfully down-staged and do well after transplantation. This article reviews the principles and published data on down-staging of hepatocellular carcinoma prior to orthotopic liver transplantation.

RECENT FINDINGS

Several groups have examined the use of loco-regional therapy such as chemoembolization and radiofrequency ablation for tumor down-staging before Orthotopic liver transplantation. According to the latest results from the University of California, San Francisco involving 61 patients with hepatocellular carcinoma exceeding Milan criteria but meeting specific criteria for tumor size and number, 70% were successfully down-staged to within Milan criteria by an intention-to-treat analysis, with no posttransplant recurrence and a 4-year posttransplant survival of 92%.

SUMMARY

Strictly defined upper limits of tumor size and number for patient inclusion, as well as criteria for response to loco-regional therapy, are essential in achieving excellent posttransplant outcome following tumor down-staging.

The progression of hepatitis B- and C-infections to chronic liver disease and hepatocellular carcinoma: presentation, diagnosis, screening, prevention, and treatment of hepatocellular carcinoma

Much information has been gained in the diagnosis and treatment of HCC during the last 15 years. Ever improving imaging technology has made nonhistologic diagnostic criteria possible, albeit controversial. Liver transplantation, resection, and RFA are considered curative options. Yet,HCC incidence is steadily rising because of limited progress on disease prevention. Accurate and cost-effective screening is necessary. Presently, only 10% to 15% of HCC patients present with a curative stage of disease. Because the field of HCC is rapidly changing, patients with HCC should be referred to liver centers with a full array of services, from surgical to oncologic. The prognosis for HCC patients will surely improve with a multidisciplinary approach to care and further clinical research. Better screening and prevention of recurrence should eventually improve survival. It is hoped that antiviral treatment studies will lower the risk of HCC, and that these changes will occur soon enough to help the many patients at risk for or diagnosed with HCC over the next several years.

Surveillance for hepatocellular carcinoma in patients with cirrhosis improves outcome

OBJECTIVE

Liver transplantation has become an effective treatment for cirrhotic patients with early-stage hepatocellular carcinoma. We hypothesized that the quality of surveillance for hepatocellular carcinoma influences prognosis by affecting access to liver transplantation.

METHODS

A total of 269 patients with cirrhosis and hepatocellular carcinoma were retrospectively categorized into 3 groups according to quality of surveillance: standard-of-care (n=172) (group 1); substandard surveillance (n=48) (group 2); and absence of surveillance in patients not recognized to be cirrhotic (n=59) (group 3).

RESULTS

Three-year survival in the 60 patients who underwent liver transplantation was 81% versus 12% for patients who did not undergo transplantation (P<.001). The percentages of patients who underwent transplantation according to tumor stage at diagnosis (T1, T2, T3, and T4) were 58%, 35%, 10%, and 1%, respectively. Hepatocellular carcinoma was diagnosed at stages 1 and 2 in 70% of patients in group 1, 37% of patients in group 2, and only 18% of patients in group 3 (P <.001). Liver transplantation was performed in 32% of patients in group 1, 13% of patients in group 2, and 7% of patients in group 3 (P<.001). Three-year survival from cancer diagnosis in patients in group 3 (12%) was significantly worse than in patients in group 1 (39%) or group 2 (27%) (each P<.05). Eighty percent of patients in group 3 had subtle abnormalities of cirrhosis on routine laboratory tests.

CONCLUSION

The quality of surveillance has a direct impact on hepatocellular carcinoma stage at diagnosis, access to liver transplantation, and survival.

Diagnosis of hepatic nodules 20 mm or smaller in cirrhosis: Prospective validation of the noninvasive diagnostic criteria for hepatocellular carcinoma

This study prospectively evaluates the accuracy of contrast-enhanced ultrasound (CEUS) and dynamic magnetic resonance imaging (MRI) for the diagnosis of nodules 20 mm or smaller detected during ultrasound (US) surveillance. We included 89 patients with cirrhosis [median age, 65 years; male 53, hepatitis C virus 68, Child-Pugh A 80] without prior hepatocellular carcinoma (HCC) in whom US detected a small solitary nodule (mean diameter, 14 mm). Hepatic MRI, CEUS, and fine-needle biopsy (gold standard) (FNB) were performed at baseline. Non-HCC cases were followed (median 23 months) by CEUS/3 months and MRI/6 months. FNB was repeated up to 3 times and on detection of change in aspect/size. Intense arterial contrast uptake followed by washout in the delayed/venous phase was registered as conclusive for HCC. Final diagnoses were: HCC (n = 60), cholangiocarcinoma (n = 1), and benign lesions (regenerative/dysplastic nodule, hemangioma, focal nodular hyperplasia) (n = 28). Sex, cirrhosis cause, liver function, and alpha-fetoprotein (AFP) levels were similar between HCC and non-HCC groups. HCC patients were older and their nodules significantly larger (P < 0.0001). First biopsy was positive in 42 of 60 HCC patients. Sensitivity, specificity, and positive and negative predictive values of conclusive profile were 61.7%, 96.6%, 97.4%, and 54.9%, for MRI, 51.7%, 93.1%, 93.9%, and 50.9%, for CEUS. Values for coincidental conclusive findings in both techniques were 33.3%, 100%, 100%, and 42%. Thus, diagnosis of HCC 20 mm or smaller can be established without a positive biopsy if both CEUS and MRI are conclusive. However, sensitivity of these noninvasive criteria is 33% and, as occurs with biopsy, absence of a conclusive pattern does not rule out malignancy. These results validate the American Association for the Study of Liver Disease (AASLD) guidelines.