Growth rate of hepatocellular carcinoma: evaluation with serial computed tomography or magnetic resonance imaging

Ablative margins in percutaneous thermal ablation of hepatic tumors: a systematic review

INTRODUCTION

This study aims to systematically review current evidence on ablative margins and correlation to local tumor progression (LTP) after thermal ablation of hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLM).

METHODS

A systematic search was performed in PubMed (MEDLINE) and Web of Science to identify all studies that reported on ablative margins (AM) and related LTP rates. Studies were assessed for risk of bias and synthesized separately per tumor type. Where possible, results were pooled to calculate risk differences (RD) as function of AM.

RESULTS

In total, 2910 articles were identified of which 43 articles were eligible for final analysis. There was high variability in AM measurement methodology across studies in terms of measurement technique, imaging modalities, and timing. Most common margin stratification was < 5 mm and > 5 mm, for which data were available in 25/43 studies (58%). Of these, all studies favored AM > 5 mm to reduce the risk of LTP, with absolute RD of 16% points for HCC and 47% points for CRLM as compared to AM < 5 mm.

CONCLUSIONS

Current evidence supports AM > 5 mm to reduce the risk of LTP after thermal ablation of HCC and CRLM. However, standardization of AM measurement and reporting is critical to allow future meta-analyses and improved identification of optimal threshold value for clinical use.

Comparative effectiveness of different hepatocellular carcinoma screening intervals or modalities: a systematic review and meta-analysis

BACKGROUND

Current guidelines recommend hepatocellular carcinoma (HCC) screening in high-risk populations. However, the ideal HCC screening interval and screening modality have not been determined. This study aimed to compare the screening efficacy among different modalities with various intervals.

METHODS

PubMed and other nine databases were searched through June 30, 2021. Binary outcomes were pooled using risk ratio (RR) with 95% confidence intervals (CIs). Survival rates were also pooled using RR with 95% CIs because most eligible studies only provided the number of survival patients instead of hazard ratio.

RESULTS

In all, 13 studies were included. Two random controlled trials (RCTs) and six cohort studies compared screening intervals for ultrasonography (US) screening and found no significant differences between shorter (3- or 4-month) and longer (6- or 12-month) screening intervals in terms of early HCC proportion, HCC significant mortality, 1-year survival rate; screening at 6-month interval significantly increased the proportion of early HCC (RR = 1.17, 95% confidence interval [CI]: 1.08-1.26) and prolonged the 5-year survival rate (RR = 1.39, 95% CI: 1.07-1.82) relative to the 12-month interval results. Three other RCTs and two cohort studies compared different screening modalities in cirrhosis or chronic hepatitis B, which indicated no statistical differences in the proportion of early HCC (RR = 0.89, 95% CI: 0.40-1.96) and HCC mortality (RR = 0.69, 95% CI: 0.23-2.09) between the biannual US and annual computed tomography (CT screening). Biannual US screening showed a lower proportion of early HCC than biannual magnetic resonance imaging (MRI) (RR = 0.60, 95% CI: 0.37-0.97) and biannual US combined with annual CT (RR = 1.31, 95% CI: 1.13-1.51) screening. The proportion of early HCC in the contrast-enhanced US group was slightly higher than that in the B-mode US (RR = 1.08, 95% CI: 1.00-1.23) group.

CONCLUSIONS

The evidence suggests that 6 months may be the best HCC screening interval for US screening. The effectiveness of CT and MRI is better than US during same screening intervals. However, MRI and CT are more expensive than US, and CT also can increase the risk of radiation exposure. The selection of CT or MRI instead of US should be carefully considered.

REGISTRATION

No. CRD42020148258 at PROSPERO website ( https://www.crd.york.ac.uk/PROSPERO/ ).

CT/MRI LI-RADS v2018 vs. CEUS LI-RADS v2017-Can Things Be Put Together?

Simple Summary

The LI-RADS system is nowadays the mainstream system used in classifying liver nodules in cirrhotic liver according to their risk of malignancy. Two main LI-RADS documents have been released—the CEUS LI-RADS v2017 document, and the CT/MRI LI-RADS v2018 document. In some circumstances, a nodule can be differently classified when using CEUS versus when using CT or MRI. In this paper, we also focus on the existing similitudes between the two documents but, essentially, on the differences between the two main documents and the complementarities between imaging techniques in characterizing liver nodules in cirrhotic livers. Awareness of the complementarity of imaging techniques may lead to an improvement in the characterization and classification of liver nodules and will reduce the number of liver biopsies. This paper proposes practical solutions in order to better classify and manage observations or nodules detected in cirrhotic livers.

Abstract

Different LI-RADS core documents were released for CEUS and for CT/MRI. Both documents rely on major and ancillary diagnostic criteria. The present paper offers an exhaustive comparison of the two documents focusing on the similarities, but especially on the differences, complementarity, and added value of imaging techniques in classifying liver nodules in cirrhotic livers. The major diagnostic criteria are defined, and the sensitivity and specificity of each major diagnostic criteria are presented according to the literature. The existing differences between techniques in assessing the major diagnostic features can be then exploited in order to ensure a better classification and a better clinical management of liver nodules in cirrhotic livers. Ancillary features depend on the imaging technique used, and their presence can upgrade or downgrade the LI-RADS score of an observation, but only as far as LI-RADS 4. MRI is the imaging technique that provides the greatest number of ancillary features, whereas CEUS has fewer ancillary features than other imaging techniques. In the final part of the manuscript, some recommendations are made by the authors in order to guidephysicians as to when adding another imaging technique can be helpful in managing liver nodules in cirrhotic livers.

Hepatocellular carcinoma tumour volume doubling time: a systematic review and meta-analysis

BACKGROUND

Tumour growth patterns have important implications for surveillance intervals, prognostication and treatment decisions but have not been well described for hepatocellular carcinoma (HCC). The aim of our study was to characterise HCC doubling time and identify correlates for indolent and rapid growth patterns.

METHODS

We performed a systematic literature review of Medline and EMBASE databases from inception to December 2019 and national meeting abstracts from 2010 to 2018. We identified studies reporting HCC tumour growth or tumour volume doubling time (TVDT), without intervening treatment, and abstracted data to calculate TVDT and correlates of growth patterns (rapid defined as TVDT <3 months and indolent as TVDT >9 months). Pooled TVDT was calculated using a random-effects model.

RESULTS

We identified 20 studies, including 1374 HCC lesions in 1334 patients. The pooled TVDT was 4.6 months (95% CI 3.9 to 5.3 months I²=94%), with 35% classified as rapid, 27.4% intermediate and 37.6% indolent growth. In subgroup analysis, studies from Asia reported shorter TVDT than studies elsewhere (4.1 vs 5.8 months). The most consistent correlates of rapid tumour growth included hepatitis B aetiology, smaller tumour size (continuous), alpha fetoprotein doubling time and poor tumour differentiation. Studies were limited by small sample sizes, measurement bias and selection bias.

CONCLUSION

TVDT of HCC is approximately 4-5 months; however, there is heterogeneity in tumour growth patterns, including more aggressive patterns in Asian hepatitis B-predominant populations. Identifying correlates of tumour growth patterns is important to better individualise HCC prognostication and treatment decisions.

Can Immediately Treating Subcentimeter Hepatocellular Carcinoma Improve the Survival of Patients?

Background

With the development of imaging technology, an increasing number of subcentimeter hepatocellular carcinoma (HCC) has been detected. How to manage these lesions remains controversial and lacks evidence. We aimed to explore whether timely treating subcentimeter HCC is necessary considering the risks of false-positives and treatment failure.

Methods

In this retrospective study, we reviewed HCC patients treated with hepatectomy or ablation in our institution. Then, we enrolled 439 HCC patients with solitary lesion measuring up to 2 cm from November 1, 2009 to June 30, 2019. The baseline and clinical characteristics of these patients were collected. The patients were classified into primary and recurrent groups. The Kaplan–Meier method with Log-rank test was performed to compare the overall survival (OS) and recurrence-free survival (RFS) between patients with subcentimeter HCC and those with HCC measuring 1–2 cm. Univariate and multivariate analyses were adopted to identify prognostic factors for survival.

Results

The OS and RFS did not differ significantly between patients with subcentimeter HCC and those with HCC measuring 1–2 cm in the primary group (p = 0.12 and 0.75). Similar results were found in the recurrent group. In multivariate analysis, the albumin-bilirubin (ALBI) grade and serum alpha fetoprotein (AFP) level were significantly associated with OS and RFS in the primary group. The serum AFP level was the only factor that correlated with OS and RFS in the recurrent group.

Conclusion

Routine screening for subcentimeter HCC is feasible. Considering uncertain diagnosis and treatment difficulties, it is more considerable to follow patients until lesions are larger than 1 cm and then provide curative treatments.

Hepatocellular Carcinoma Demonstrates Heterogeneous Growth Patterns in a Multicenter Cohort of Patients With Cirrhosis

BACKGROUND AND AIMS

There are limited data on hepatocellular carcinoma (HCC) growth patterns, particularly in Western cohorts, despite implications for surveillance, prognosis, and treatment. Our study's aim was to quantify tumor doubling time (TDT) and identify correlates associated with indolent and rapid growth.

APPROACH AND RESULTS

We performed a retrospective multicenter cohort study of patients with cirrhosis diagnosed with HCC from 2008 to 2017 at six US and European health systems with two or more contrast-enhanced imaging studies performed ≥ 30 days apart prior to HCC treatment. Radiologists independently measured tumors in three dimensions to calculate TDT and specific growth rate (SGR). We used multivariable ordinal logistic regression to identify factors associated with indolent (TDT > 365 days) and rapid (TDT < 90 days) tumor growth. In the primary cohort (n = 242 patients from four centers), median TDT was 229 days (interquartile range [IQR], 89-627) and median SGR was 0.3% per day (IQR, 0.1%-0.8%). Over one-third (38%) of HCCs had indolent growth, 36.8% intermediate growth, and 25.2% rapid growth. In multivariable analysis, indolent growth was associated with larger tumor diameter (odds ratio [OR], 1.15, 95% confidence interval [CI], 1.03-1.30) and alpha-fetoprotein < 20 ng/mL (OR, 1.90; 95% CI, 1.12-3.21). Indolent growth was more common in nonviral than viral cirrhosis (50.9% versus 32.1%), particularly in patients with T1 HCC (OR, 3.41; 95% CI, 1.08-10.80). Median TDT (169 days; IQR 74-408 days) and SGR (0.4% per day) were similar in an independent cohort (n = 176 patients from two centers).

CONCLUSIONS

In a large Western cohort of patients with HCC, we found heterogeneous tumor growth patterns, with one-fourth exhibiting rapid growth and over one-third having indolent growth. Better understanding different tumor growth patterns may facilitate a precision approach to prognostication and treatment.

Status of, and strategies for improving, adherence to HCC screening and surveillance

Hepatocellular carcinoma (HCC) represents the second leading cause of cancer deaths worldwide and the main cause of death in patients with cirrhosis. Secondary prevention of HCC can be accomplished through the serial application of screening tests (ultrasound with or without alpha-fetoprotein) to detect the presence of subclinical lesions amenable to potentially curative treatment, such as surgery and ablation. The efficacy of HCC screening is accepted by hepatologists in terms of decline in cancer-specific mortality, but its translation into clinical practice is less than ideal. The effectiveness of HCC screening is hampered by several factors: failure to identify at-risk patients, failure to access care and failure to detect HCC. For each of these steps, possible improvements are discussed in order to face the changing etiology of cirrhosis and expand the screening of at-risk populations by including selected nonalcoholic fatty liver disease patients.

The Optimal Management for Sub-Centimeter Hepatocellular Carcinoma: Curative Treatments or Follow-Up?

Background

The optimal strategy for dealing with sub-centimeter hepatic nodules has not yet been established. This study aimed to assess whether there was a need to provide curative treatments for sub-centimeter hepatocellular carcinomas (HCCs) to patients at risk for high false positives.

Material/Methods

We identified patients with primary pathologically diagnosed HCC ≤2 cm from 2004 to 2015 in the Surveillance, Epidemiology and End Results (SEER) database. They were divided according to the interventions they received: local ablation, surgical resection, or liver transplantation. In each group, overall survival and cancer-specific survival were used as endpoints to compare the prognoses between patients with sub-centimeter HCC and patients with HCC measuring 1 to 2 cm by Kaplan-Meier. Propensity score matching was performed to reduce bias. We also compared the survival of patients with a primary solitary HCC based on interventions, in the different tumor size groups. Bootstrapping was performed to validate the findings.

Results

Overall, 10.4% of patients (197 out of 1894) had HCCs <1 cm, and 89.6% of patients (1697 out of 1894) had HCCs in the 1 to 2 cm range. There was no significant difference in overall and cancer-specific survival between patients with HCCs <1 cm and those with HCCs in the 1 to 2 cm range, in all treatment groups. After adjusting confounding factors, no significant correlation was found between tumor size and survival time. In patients with HCCs measuring ≤2 cm, overall survival and cancer-specific survival were superior in liver transplantation compared with surgical resection and local ablation. Surgical resection provided better survival than local ablation.

Conclusions

Compared to patients with HCCs measuring 1 to 2 cm, the survival rates of patients with sub-centimeter HCCs was not improved through curative treatments, risking high false positives.

Thiamin Regresses the Anticancer Efficacy of Methotrexate in the Amelioration of Diethyl Nitrosamine-Induced Hepatocellular Carcinoma in Wistar Strain Rats

Background: Hepatocellular carcinoma (HCC) is the most common primary liver cancer and occurs frequently in patients with liver cirrhosis. HCC is the leading cause of cancer-related mortality around the globe.Aim: This study assessed the effects of thiamin in the anticancer activity of methotrexate (MTX) in diethyl nitrosamine (DEN) induced hepatocellular Carcinoma in Wistar strain male rats.Method: Fifty rats were randomly segregated in five groups with 10 rats in each group. HCC was induced by single intraperitoneal (i.p) dose of DEN (200 mg/kg) and HCC promoter phenobarbital was used in the basal diet (0.05%) for 5 days per week until the termination of the study in all the rats except for the normal control (NC) group. Disease control (DC) was given no treatment, while DM (DEN + MTX) and DT (DEN + thiamin) groups were given MTX (5 mg/kg, i.p per week for 16 weeks) and thiamin (25 mg/kg, orally, daily for 16 weeks), respectively. DMT (DEN + MTX + thiamin) group was given the combined dose of MTX and thiamin. Histopathological study was carried out to confirm the liver function tests such as α-feto protein (AFP), alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TB), and total protein (TP) along with antioxidants vascular endothelial growth factor (VEGF), lipid per-oxidation (LPO), superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT).Results: Results showed that liver biomarkers and antioxidants parameters were still abnormal in the DC group while DM group showed significant restoration, but DT group showed less significant normalization. DMT showed mild recovery of these parameters.Conclusion: The mechanism of action of MTX and thiamin is antiparallel to each other and hence their concomitant administration may lead to inefficient anticancer activity of MTX.

Cost-Utility Analysis of Imaging for Surveillance and Diagnosis of Hepatocellular Carcinoma

OBJECTIVE. The purpose of this study is to compare imaging-based surveillance and diagnostic strategies in patients at risk for hepatocellular carcinoma (HCC) while taking into account technically inadequate examinations and patient compliance. MATERIALS AND METHODS. A Markov model simulated seven strategies for HCC surveillance and diagnosis in patients with cirrhosis: strategy A, ultrasound (US) for surveillance and CT for diagnosis; strategy B, US for surveillance and complete MRI for diagnosis; strategy C, US for surveillance and CT for inadequate or positive surveillance; strategy D, US for surveillance and complete MRI for inadequate or positive surveillance; strategy E, surveillance and diagnosis with CT followed by complete MRI for inadequate surveillance; strategy F, surveillance and diagnosis with complete MRI followed by CT for inadequate surveillance; and strategy G, surveillance with abbreviated MRI followed by CT for inadequate surveillance or complete MRI for positive surveillance. Two compliance scenarios were evaluated: optimal and conservative. For each scenario, the most cost-effective strategy was based on a willingness-to-pay threshold of $50,000 (Canadian) per quality-adjusted life year (QALY). Sensitivity analyses were performed. RESULTS. Base-case analysis revealed that strategy E was the most cost-effective when compliance was optimal ($13,631/QALY), and strategy G was the most cost-effective when compliance was conservative ($39,681/QALY). Sensitivity analyses supported the base-case analysis in the optimal compliance scenario, but several parameters altered the most cost-effective strategy in the conservative compliance scenario. CONCLUSION. In an optimal compliance scenario, CT for HCC surveillance and diagnosis and complete MRI for inadequate CT was most cost-effective. In a conservative compliance scenario, abbreviated MRI may be an alternative to US-based surveillance.

Multiscale systems pharmacological analysis of everolimus action in hepatocellular carcinoma

Dysregulation of mTOR pathway is common in hepatocellular carcinoma (HCC). A translational quantitative systems pharmacology (QSP), pharmacokinetic (PK), and pharmacodynamic (PD) model dissecting the circuitry of this pathway was developed to predict HCC patients' response to everolimus, an mTOR inhibitor. The time course of key signaling proteins in the mTOR pathway, HCC cells viability, tumor volume (TV) and everolimus plasma and tumor concentrations in xenograft mice, clinical PK of everolimus and progression free survival (PFS) in placebo and everolimus-treated patients were extracted from literature. A comprehensive and multiscale QSP/PK/PD model was developed, qualified, and translated to clinical settings. Model fittings and simulations were performed using Monolix software. The S6-kinase protein was identified as critical in the mTOR signaling pathway for describing everolimus lack of efficacy in HCC patients. The net growth rate constant (kg) of HCC cells was estimated at 0.02 h^-1 (2.88%RSE). The partition coefficient of everolimus into the tumor (kp) was determined at 0.06 (12.98%RSE). The kg in patients was calculated from the doubling time of TV in naturally progressing HCC patients, and was determined at 0.004 day^-1. Model-predicted and observed PFS were in good agreement for placebo and everolimus-treated patients. In conclusion, a multiscale QSP/PK/PD model elucidating everolimus lack of efficacy in HCC patients was successfully developed and predicted PFS reasonably well compared to observed clinical findings. This model may provide insights into clinical response to everolimus-based therapy and serve as a valuable tool for the clinical translation of efficacy for novel mTOR inhibitors.

Predictors of failure to detect early hepatocellular carcinoma in patients with chronic hepatitis B who received regular surveillance

BACKGROUND

A proportion of chronic hepatitis B (CHB) patients are diagnosed with advanced hepatocellular carcinoma (HCC) despite regular surveillance.

AIMS

To determine predictors for HCC detection failure in CHB patients who underwent regular surveillance.

METHODS

CHB patients with well-preserved liver function, who underwent ultrasonography and alpha-foetoprotein (AFP) analysis every 6 months, were enrolled. Cox regression analysis was used to identify predictors for detection failure, defined as HCC initially diagnosed at Barcelona Clinic Liver Cancer (BCLC) stage B or C.

RESULTS

Of the 4590 CHB patients (mean age, 52.1 years; men, 61.6%), 169 patients were diagnosed with HCC (3.68%) and 35 (20.7%) HCC patients were initially diagnosed with HCC BCLC stage B or C. The cumulative incidence of HCC detection failure was 0.2% at year 1 and 1.3% at year 5. Multivariate analyses indicated that cirrhosis (hazard ratio [HR], 3.078; 95% CI, 1.389-6.821; P = 0.006), AFP levels ≥9 ng/mL (HR, 5.235; 95% CI, 2.307-11.957; P = 0.010), and diabetes mellitus (HR, 3.336; 95% CI, 1.341-8.296; P = 0.010) were independent predictors of HCC detection failure. Another model that incorporated liver stiffness (LS) values identified LS values ≥11.7 kPa (HR, 11.045; 95% CI, 2.066-59.037; P = 0.005) and AFP levels ≥9 ng/mL (HR, 4.802; 95% CI, 1.613-14.297; P = 0.005) as predictors of detection failure.

CONCLUSIONS

In CHB patients undergoing regular surveillance with ultrasonography and alpha-foetoprotein (AFP) analysis every 6 months, the HCC detection failure rate was not high (0.8% per person; 0.1% per test). However, careful attention should be paid in patients with advanced liver fibrosis (clinical cirrhosis or LS value >11.7 kPa), high AFP levels, or diabetes mellitus, who are prone to surveillance failure.

Risk factors and prevention of hepatocellular carcinoma in the era of precision medicine

Patients who develop chronic fibrotic liver disease, caused by viral or metabolic aetiologies, are at a high risk of developing hepatocellular carcinoma (HCC). Even after complete HCC tumour resection or ablation, the carcinogenic tissue microenvironment in the remnant liver can give rise to recurrent de novo HCC tumours, which progress into incurable, advanced-stage disease in most patients. Thus, early detection and prevention of HCC development is, in principle, the most impactful strategy to improve patient prognosis. However, a "one-size-fits-all" approach to HCC screening for early tumour detection, as recommended by clinical practice guidelines, is utilised in less than 20% of the target population, and the performance of screening modalities, including ultrasound and alpha-fetoprotein, is suboptimal. Furthermore, optimal screening strategies for emerging at-risk patient populations, such as those with chronic hepatitis C after viral cure, or those with non-cirrhotic, non-alcoholic fatty liver disease remain controversial. New HCC biomarkers and imaging modalities may improve the sensitivity and specificity of HCC detection. Clinical and molecular HCC risk scores will enable precise HCC risk prediction followed by tailoured HCC screening of individual patients, maximising cost-effectiveness and optimising allocation of limited medical resources. Several aetiology-specific and generic HCC chemoprevention strategies are evolving. Epidemiological and experimental studies have identified candidate chemoprevention targets and therapies, including statins, anti-diabetic drugs, and selective molecular targeted agents, although their clinical testing has been limited by the lengthy process of cancer development that requires long-term, costly studies. Individual HCC risk prediction is expected to overcome the challenge by enabling personalised chemoprevention, targeting high-risk patients for precision HCC prevention and substantially improving the dismal prognosis of HCC.

Accuracy of the diagnostic evaluation of hepatocellular carcinoma with LI-RADS

Background There are few studies about the Liver Imaging Reporting and Data System (LI-RADS), which was developed with the purpose of standardizing the interpretation and reporting of liver imaging examinations in patients at risk for hepatocellular carcinoma (HCC). Purpose To evaluate the diagnostic accuracy of HCC diagnosis using LI-RADS. Material and Methods The computed tomography (CT), magnetic resonance imaging (MRI), and clinical data of 297 lesions in 249 patients between June 2012 and August 2013 were retrospectively analyzed. Using LI-RADS 2014, two radiologists evaluated the lesions and a LI-RADS category was retrospectively assigned to each nodule. Results The final diagnoses of 297 nodules in 249 patients consisted of 191 malignant and 106 benign lesions. Out of 44 LI-RADS category 1 lesions, none were HCCs. However, 2/25 category 2 lesions, 3/35 category 3 lesions, 16/25 category 4 lesions, 151/156 category 5 lesions, and 3/12 category LRM/OM (probable malignancy, not specific for HCC/other malignancy) lesions were HCCs. The Kappa value was 0.44 (95% confidence interval [CI] = 0.39-0.49) between two observers during LI-RADS grading. Conclusion The negative predictive value of LI-RADS category 1 was 100%. In addition, a relevant proportion of lesions categorized as category 2 or 3, or even as other malignancies, were HCCs. LI-RADS category 5 had a high specificity for HCC. LI-RADS was not able to give a differential diagnosis for the false-positive lesions of LI-RADS category 5.

LI-RADS® ancillary features on CT and MRI

The Liver Imaging Reporting and Data System (LI-RADS) uses an algorithm to assign categories that reflect the probability of hepatocellular carcinoma (HCC), non-HCC malignancy, or benignity. Unlike other imaging algorithms, LI-RADS utilizes ancillary features (AFs) to refine the final category. AFs in LI-RADS v2017 are divided into those favoring malignancy in general, those favoring HCC specifically, and those favoring benignity. Additionally, LI-RADS v2017 provides new rules regarding application of AFs. The purpose of this review is to discuss ancillary features included in LI-RADS v2017, the rationale for their use, potential pitfalls encountered in their interpretation, and tips on their application.

LI-RADS major features: CT, MRI with extracellular agents, and MRI with hepatobiliary agents

The Liver Imaging Reporting and Data System (LI-RADS) was designed to standardize the interpretation and reporting of observations seen on studies performed in patients at risk for development of hepatocellular carcinoma (HCC). The LI-RADS algorithm guides radiologists through the process of categorizing observations on a spectrum from definitely benign to definitely HCC. Major features are the imaging features used to categorize observations as LI-RADS 3 (intermediate probability of malignancy), LIRADS 4 (probably HCC), and LI-RADS 5 (definite HCC). Major features include arterial phase hyperenhancement, washout appearance, enhancing capsule appearance, size, and threshold growth. Observations that have few major criteria are assigned lower categories than those that have several, with the goal of preserving high specificity for the LR-5 category of Definite HCC. The goal of this paper is to discuss LI-RADS major features, including definitions, rationale for selection as major features, and imaging examples.

The role of liver resection in the management of intermediate and advanced stage hepatocellular carcinoma. A systematic review

BACKGROUND

The ideal management for patients with intermediate and advanced stage hepatocellular carcinoma (HCC) is controversial. The main purpose of this systematic review is to examine the role of liver resection in patients with intermediate stage HCC (multinodular HCCs) and in advanced stage HCC [mainly patients with portal vein tumor thrombosis (PVTT)].

METHODS

A systematic search of the literature was performed in Pud Med and the Cochrane Library from 01.01.2000 to 30.06.2016.

RESULTS

Twenty-three articles with 2412 patients with multinodular HCCs were selected. Also, 29 studies with 3659 patients with HCCs with macrovascular invasion were selected. In patients with multinodular HCCs the median post-operative morbidity was 25% and the 90-day mortality was 2.7%. The median survival was 37 months and the 5-year survival 35%. The 5-year survival was much better for patients with a number of HCCs ≤3 vs. HCCs >3 (49% vs. 23%). In patients with macrovascular invasion, who underwent hepatic resection, the median post-operative morbidity was 33% and the in-hospital mortality 2.7%. The median survival was 15 months. The 3 and 5year survival was 33% and 20% respectively. Moreover a significant difference in survival was noted according to PVTT stage: 5- year survival for distal PVTT, PVTT of the main intrahepatic PV branch and PVTT extending to the main PV was 45%, 19% and 14.5% respectively.

CONCLUSIONS

Liver resection in patients with multinodular HCCs and HCCs with PVTT offers satisfactory long-term survival and should be considered in selected patients.

Benign nodules in post-Fontan livers can show imaging features considered diagnostic for hepatocellular carcinoma

PURPOSE

To describe the imaging appearance of hyperenhancing nodules arising in post-Fontan patients and to identify specific features best correlated with malignancy.

METHODS

Hyperenhancing hepatic nodules visible on CT and/or MRI in post-Fontan patients were identified retrospectively and reviewed by subspecialty radiologists. Nodules with characteristic imaging findings of focal nodular hyperplasia (FNH) were defined as typical, the remainder were defined as atypical, described in detail according to LIRADS criteria, and length of stability over time was recorded. Clinical data, alpha fetoprotein levels (AFP), central venous pressures (CVP), and histopathology were recorded.

RESULTS

245 hyperenhancing nodules (215 typical, 30 atypical) were evaluated in 30 patients. Twenty-nine atypical nodules showed washout (portal phase in 6, delayed phase in 29), 0 showed pseudocapsule, 1 showed threshold growth, 1 showed tumor in vein, and 5 showed ancillary features favoring malignancy. Pathology confirmed hepatocellular carcinoma (HCC) in 3 atypical nodules and FNH-like histology in 3 atypical and 4 typical nodules. 2 atypical nodules were present in a patient with clinical diagnosis of HCC. 20 nodules (7 typical, 13 atypical due to washout) were studied with hepatobiliary contrast agent and all showed homogenous hepatobiliary phase retention. Atypical nodules were significantly more likely to be HCC than biopsy-proven FNH-like or stable ≥24 months when showing portal phase washout (P < 0.001), mosaic architecture (P = 0.020) or in the presence of cirrhosis (P = 0.004) or elevated AFP (P = 0.004). Atypical nodules that were HCC had higher median CVP than those that were FNH-like (19, range 16-27 vs. 13, range 12-16 mmHg, P = 0.0003), there was not a significant difference based on median patient age (HCC 30, range 10-41 vs. FNH-like 40 range 10-41, P = 0.244).

CONCLUSIONS

Benign hyperenhancing masses in Fontan patients may demonstrate washout and be mistaken for HCC by imaging criteria. Portal phase washout, mosaic architecture, elevated AFP and higher CVP were associated with HCC in the atypical nodules found in this population.

Overdiagnosis: An Understudied Issue in Hepatocellular Carcinoma Surveillance

Overdiagnosis, the detection of clinically insignificant disease that would not otherwise impact the patient's lifespan, is a phenomenon that has been described in several solid tumors, such as prostate, breast, thyroid, and lung cancers. Population-based efforts to reduce hepatocellular carcinoma (HCC) mortality in cirrhosis patients by screening and early detection may result in the overdiagnosis of HCC. One of the harms of overdiagnosis is subsequent overtreatment, which can result in increased costs, as well as physical side effects, psychological harms, and poorer quality of life. In this review, the authors explore the potential for overdiagnosis in HCC.

Tumor Volume Doubling Time as a Dynamic Prognostic Marker for Patients with Hepatocellular Carcinoma

BACKGROUND AND AIMS

To evaluate the clinical value of tumor growth rate in hepatocellular carcinoma (HCC) patients, we investigated the growth rate of HCC by calculating the tumor volume doubling time (TVDT) and its impact on survival and recurrence.

METHODS

A retrospective cohort study of 269 HCC patients who underwent two or more pretreatment imaging studies of computed tomography or magnetic resonance imaging was performed. Tumor growth rate and TVDT were calculated by comparing tumor volumes between imaging studies. Clinical parameters independently related to a TVDT of <2 months were evaluated. After dividing patients into slow-growing (159 patients with TVDT >2 months) and rapid-growing (110 patients with TVDT <2 months) groups, we compared the groups in terms of their survival and recurrence outcomes. The response to transarterial chemoembolization (TACE) was evaluated according to TVDT.

RESULTS

The median tumor growth rate and TVDT were 37.5%/month and 2.37 months, respectively. By logistic regression analyses, a high Child-Pugh score, small initial tumor diameter, gross vascular invasion, and tumor multiplicity were found to be independently associated with a TVDT of <2 months (P < 0.05). Patients in the rapid-growing group had lower survival rates and higher recurrence rates (P < 0.05). The response to TACE was worse in the rapid-growing group (P < 0.05).

CONCLUSIONS

A fast HCC growth rate is associated with poor liver function and aggressive tumor biology. HCC patients with shorter TVDTs exhibit poorer survival and recurrence outcomes as well as a poor response to TACE.

Tailored algorithms for hepatocellular carcinoma surveillance: Is one-size-fits-all strategy outdated?

PURPOSE OF REVIEW

Current clinical practice guidelines recommend regular hepatocellular carcinoma (HCC) surveillance with biannual ultrasound with or without serum alpha-fetoprotein uniformly applied to all patients with cirrhosis. However, clinical implementation of this one-size-fits-all strategy has been challenging as evidenced by very low application rate below 20% due to various reasons, including suboptimal performance of the surveillance modalities.

RECENT FINDINGS

Newly emerging imaging techniques such as abbreviated MRI (AMRI) and molecular HCC risk biomarkers have increasingly become available for clinical evaluation and implementation. These technologies may have a potential to reshape HCC surveillance by enabling tailored strategies. This would involve performing optimized surveillance tests according to individual HCC risk, and allocating limited medical resources for HCC surveillance based on cost-effectiveness.

SUMMARY

Tailored HCC surveillance could lead to achievement of precision HCC care and substantial improvement of the current dismal patient prognosis.

Length time bias in surveillance for hepatocellular carcinoma and how to avoid it

AIM

Length time bias is a selection bias which can lead to an overestimation of survival of screening-detected cases caused by the relative excess of slower-growing tumors detected with respect to symptomatic cases. This leads to the incorrect perception that screening improves outcomes when it only selects tumors with a favorable biology. Data regarding this bias in surveillance for hepatocellular carcinoma (HCC) have never been provided.

METHODS

A semi-Markov model was developed to investigate this issue. An exponential tumor growth was applied. During its growth, tumor diagnosis "at surveillance appointments" was made when tumor attained a size equal to or above the size of tumors diagnosed in surveilled patients obtained from pertinent published reports, or "in-between appointments" (due to the development of symptoms) if tumor size attained the size of symptomatic diagnosis, derived from published reports; otherwise the tumor continued to grow until the time horizon had been reached. Tumor doubling time (DT) values were recorded according to the method of diagnosis.

RESULTS

In a theoretical cohort of 1000 patients submitted to semiannual surveillance, 72.5% will be diagnosed at a surveillance appointment and 18% because of symptom development, although under surveillance. Patients diagnosed with HCC at a surveillance appointment had a median tumor DT of 100 days (interquartile range, 68-143 days), whereas those diagnosed because of symptoms had a median DT of 42 days (interquartile range, 29-58 days) although under surveillance.

CONCLUSION

The surveillance propensity to detect slower-growth tumors is relevant, and practical suggestions to minimize this bias in longitudinal studies are provided.

Bridging Sunitinib Exposure to Time-to-Tumor Progression in Hepatocellular Carcinoma Patients With Mathematical Modeling of an Angiogenic Biomarker

Hepatocellular carcinoma (HCC) is third in cancer-related causes of death worldwide and its treatment is a significant unmet medical need. Sunitinib is a selective tyrosine kinase inhibitor of the angiogenic biomarker: soluble vascular endothelial growth factor receptor-2 (sVEGFR2 ). Sunitinib failed its primary overall survival endpoint in patients with advanced HCC in a phase III trial compared to sorafenib. In the present study, pharmacokinetic-pharmacodynamic modeling was used to link drug-exposure to tumor-growth-inhibition (TGI) and time-to-tumor progression (TTP) through sVEGFR2 dynamics. The results suggest that 1) active drug concentration (i.e., sunitinib and its metabolite) inhibits the release of sVEGFR2 and that such inhibition is associated with TGI, and 2) daily sVEGFR2 exposure is likely a reliable predictor for the TTP in HCC patients. Moreover, the model quantitatively links the dynamics of an angiogenesis biomarker to TTP and accurately predicts observed literature-reported results of placebo treatment.

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.

Multiparametric MRI of the prostate: diagnostic performance and interreader agreement of two scoring systems

OBJECTIVE

To compare the diagnostic accuracies and interreader agreements of the Prostate Imaging Reporting and Data System (PI-RADS) v. 2 and University of California San Francisco (UCSF) multiparametric prostate MRI scale for diagnosing clinically significant prostate cancer.

METHODS

This institutional review board-approved retrospective study included 49 males who had 1.5 T endorectal MRI and prostatectomy. Two radiologists scored suspicious lesions on MRI using PI-RADS v. 2 and the UCSF scale. Percent agreement, 2 × 2 tables and the area under the receiver operating characteristic curves (Az) were used to assess and compare the individual and overall scores of these scales. Interreader agreements were estimated with kappa statistics.

RESULTS

Reader 1 (R1) detected 78 lesions, and Reader 2 (R2) detected 80 lesions. Both identified 52 of 65 significant cancers. The Az for PI-RADS v. 2 and UCSF scale for R1 were 0.68 and 0.69 [T2 weighted imaging (T2WI)], 0.75 and 0.68 [diffusion-weighted imaging (DWI)] and 0.64 and 0.72 (overall score), respectively, and were 0.72 and 0.75 (T2WI), 0.73 and 0.67 (DWI) and 0.66 and 0.75 (overall score) for R2. The dynamic contrast-enhanced percent agreements between scales were 100% (R1) and 95% (R2). PI-RADS v. 2 DWI of R1 performed better than UCSF DWI (Az = 0.75 vs Az = 0.68; p = 0.05); no other differences were found. The interreader agreements were higher for PI-RADS v. 2 (T2WI: 0.56 vs 0.42; DWI: 0.60 vs 0.46; overall: 0.61 vs 0.42). The UCSF approach to derive the overall PI-RADS v. 2 scores increased the Az for the identification of significant cancer (R1 to 0.76, p < 0.05; R2 to 0.71, p = 0.35).

CONCLUSION

Although PI-RADS v. 2 DWI score may have a higher discriminatory performance than the UCSF scale counterpart to diagnose clinically significant cancer, the utilization of the UCSF scale weighing system for the integration of PI-RADS v. 2 individual parameter scores improved the accuracy its overall score.

ADVANCES IN KNOWLEDGE

PI-RADS v. 2 is moderately accurate for the identification of clinically significant prostate cancer, but the utilization of alternative approaches to derive the overall PI-RADS v. 2 score, including the one used by the UCSF system, may improve its diagnostic accuracy.

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.

Surveillance for hepatocellular carcinoma is associated with increased survival: Results from a large cohort in the Netherlands

BACKGROUND & AIMS

Effectiveness of surveillance for hepatocellular carcinoma is controversial. We here explore its effects in "real life" clinical practice.

METHODS

Patients with hepatocellular carcinoma diagnosed in the period 2005-2012 in five Dutch academic centers were evaluated. Surveillance was defined as ⩾2 screening tests during three preceding years and at least one radiologic imaging test within 18 months before diagnosis.

RESULTS

295 (27%) of 1074 cases underwent surveillance. Median time interval between last negative radiologic imaging and hepatocellular carcinoma diagnosis was 7.5 months. In the surveillance group, cirrhosis (97% vs. 60%, p<0.001) and viral hepatitis were more frequent, and non-alcoholic fatty liver disease or absence of risk factors less frequent. In case of surveillance, tumor size was significantly smaller (2.7 vs. 6.0 cm), with lower alpha-fetoprotein levels (16 vs. 44 μg/L), earlier tumor stage (BCLC 0 and A combined: 61% vs. 21%) and resection/transplantation (34% vs. 25%) or radiofrequency ablation (23% vs. 7%) more often applied, with significantly higher 1-, 3-, and 5-year survival rates. Survival benefit by surveillance remained significant after adjustment for lead-time bias based on assumed tumor doubling time of 90 days, but not with doubling time of ⩾120 days. In multivariate analysis, surveillance was an independent predictor for mortality (for interval ⩽9 respectively >9 months: adjusted HRs 0.51 and 0.50, 95% confidence intervals: 0.39-0.67 and 0.37-0.69).

CONCLUSIONS

Surveillance for hepatocellular carcinoma was associated with smaller tumor size, earlier tumor stage, with an impact on therapeutic strategy and was an independent predictor of survival.

Growth rate of early-stage hepatocellular carcinoma in patients with chronic liver disease

Background/Aims

The goal of this study was to estimate the growth rate of hepatocellular carcinoma (HCC) and identify the host factors that significantly affect this rate.

Methods

Patients with early-stage HCC (n=175) who underwent two or more serial dynamic imaging studies without any anticancer treatment at two tertiary care hospitals in Korea were identified. For each patient, the tumor volume doubling time (TVDT) of HCC was calculated by comparing tumor volumes between serial imaging studies. Clinical and laboratory data were obtained from the medical records of the patients.

Results

The median TVDT was 85.7 days, with a range of 11 to 851.2 days. Multiple linear regression revealed that the initial tumor diameter (a tumor factor) and the etiology of chronic liver disease (a host factor) were significantly associated with the TVDT. The TVDT was shorter when the initial tumor diameter was smaller, and was shorter in HCC related to hepatitis B virus (HBV) infection than in HCC related to hepatitis C virus (HCV) infection (median, 76.8 days vs. 137.2 days; P=0.0234).

Conclusions

The etiology of chronic liver disease is a host factor that may significantly affect the growth rate of early-stage HCC, since HBV-associated HCC grows faster than HCV-associated HCC.

Subcentimeter hypervascular nodule with typical imaging findings of hepatocellular carcinoma in patients with history of hepatocellular carcinoma: natural course on serial gadoxetic acid-enhanced MRI and diffusion-weighted imaging

OBJECTIVES

To evaluate the natural course of subcentimeter hypervascular nodules at high risk for developing into hepatocellular carcinomas (SHNHR) using serial magnetic resonance imaging (MRI) in patients with a history of hepatocellular carcinoma (HCC).

METHODS

An SHNHR was defined as a subcentimeter hypervascular nodule having typical imaging findings of HCC on gadoxetic acid-enhanced MRI and diffusion-weighted imaging. We included 39 patients with 46 SHNHRs (mean size ± standard deviation, 6.1 ± 1.6 mm; range, 3.2 - 9.0 mm). Overt HCC was defined as pathology proven HCC or a nodule larger than 1 cm with typical imaging findings of HCC. The cumulative rate and the independent predictive factors for progression to overt HCC were evaluated.

RESULTS

The median follow-up period was 139 days (range, 64 - 392 days). The cumulative progression rate to overt HCC at 3, 6, 9, and 12 months was 13.9%, 61.7%, 83.2%, and 89.9%. The initial size of SHNHR was a significant predictor of progression to overt HCC, with an optimal cut-off value of 5.5 mm.

CONCLUSION

The progression rate of SHNHR to overt HCC within 12 months was high (89.9%) in patients with history of HCC. The initial size of SHNHR was an important predictor for progression to overt HCC.

KEY POINTS

• Most SHNHRs (89.9%) progressed to overt HCCs within 12 months. • Initial size was an important predictor for progression to overt HCCs. • The optimal cut-off value for initial nodule size was 5.5 mm.

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.

Retrospective cohort study of portacaval lymphadenopathy identified on multidetector CT and implications for follow-up

PURPOSE

Portacaval lymphadenopathy (PCLA) is common in cirrhosis and chronic viral hepatitis and is frequently an incidental finding on abdominal CT scans. We aimed to detect the incidence of malignancy in organs drained by portacaval nodes in patients with PCLA associated with cirrhosis or chronic viral hepatitis, or incidentally detected PCLA.

METHODS

We searched CT reports from 2005 to 2007 for the phrases "periportal node" and "portacaval node." MDCTs of patients with portacaval nodes ≥10 mm in maximal short-axis size on contrast-enhanced MDCTs, were included. Records were reviewed for presence of malignancy, liver metastases, chronic viral hepatitis, and cirrhosis. Clinical or imaging follow-up ≥6 months was performed to detect if malignancy developed in organs drained by portacaval nodes in patients with incidental PCLA, cirrhosis, or chronic viral hepatitis.

RESULTS

479 patients met inclusion criteria [298 males (62%), mean age 61.4 years]. In 285 (59.5%) patients, PCLA was explained by local pathology or systemic lymphadenopathy. PCLA was incidental in 146 (30.5%) patients. Of these, 112 (76.7%) had ≥6 months of follow-up (median 26 months). No patient with incidental PCLA developed malignancy in organs drained by these nodes. Cirrhosis or chronic viral hepatitis was present in 48 (10.0%) patients. Of these, 42 (87.5%) had ≥6 months follow-up (median 28 months), and only 1 patient developed cholangiocarcinoma (positive predictive value 2.4%).

CONCLUSIONS

Development of malignancy is rare in patients with PCLA, either incidental or secondary to cirrhosis or chronic viral hepatitis. Our study suggests that no follow-up of PCLA is required in these settings.

Small hepatocellular carcinoma: MRI findings for predicting tumor growth rates

RATIONALE AND OBJECTIVES

Current clinical practice favors imaging rather than biopsy to diagnose hepatocellular carcinoma (HCC). There is a need to better understand tumor biology and aggressiveness of HCC. Our goal is to investigate magnetic resonance imaging (MRI) features of HCC that are associated with faster growth rates (GRs).

MATERIALS AND METHODS

After approval from institutional review board, a retrospective evaluation was performed of pre-liver transplant patients. Fifty-two patients who developed a >2 cm HCC on serial imaging were included in the study group, with a total of 60 HCCs seen. Precursor foci were identified on serial MRIs before the specific diagnostic features of >2 cm HCC could be made, and GRs and MRI features, including signal on T1- and T2-weighted images (WI), the presence of intralesional steatosis on chemical shift imaging, and enhancement pattern were analyzed. GRs were correlated with imaging features.

RESULTS

The average GR of precursor lesions to >2 cm HCC was determined to be 0.23 cm/mo (standard deviation [SD], 0.32), with a doubling time of 5.26 months (SD, 5.44). The presence of increased signal intensity (SI) on T2-WI was associated with significantly higher growth (P = .0002), whereas increased intensity on T1-WI at the initial study was associated with a significantly lower GR (P = .0162). Furthermore, lesions with hypervascular enhancement with washout pattern had significantly higher GR (P = .0164). There is no evidence of differences in GRs seen in lesions with steatosis.

CONCLUSIONS

Small precursor lesions with increased SI on T2-WI and a washout pattern of enhancement are associated with faster GRs, which may suggest more aggressive tumor biology. These features may be helpful in patient management and surveillance for HCC.

Surveillance for hepatocellular carcinoma

When hepatocellular carcinoma presents with symptoms cure is seldom possible and death usually follows within months. However, it is possible to detect HCC early, at which stage it is curable. This requires a surveillance program. The components of such a program include: identification of the at risk population, provision of appropriate surveillance tests, and an appropriate method of determining whether the abnormalities found on screening are cancer or not. Surveillance for liver cancer meets all these criteria. Unfortunately high quality evidence showing benefit of liver cancer surveillance is lacking, but lesser quality evidence is plentiful, including several cost efficacy analyses that all show that surveillance does decrease mortality. Therefore all the continental liver disease societies and all national liver disease societies have recommended that surveillance should be undertaken.

Estimation of lead-time bias and its impact on the outcome of surveillance for the early diagnosis of hepatocellular carcinoma

BACKGROUND & AIMS

Lead-time is the time by which diagnosis is anticipated by screening/surveillance with respect to the symptomatic detection of a disease. Any screening program, including surveillance for hepatocellular carcinoma (HCC), is subject to lead-time bias. Data regarding lead-time for HCC are lacking. Aims of the present study were to calculate lead-time and to assess its impact on the benefit obtainable from the surveillance of cirrhotic patients.

METHODS

One-thousand three-hundred and eighty Child-Pugh class A/B patients from the ITA.LI.CA database, in whom HCC was detected during semiannual surveillance (n = 850), annual surveillance (n = 234) or when patients came when symptomatic (n = 296), were selected. Lead-time was estimated by means of appropriate formulas and Monte Carlo simulation, including 1000 patients for each arm.

RESULTS

The 5-year overall survival after HCC diagnosis was 32.7% in semiannually surveilled patients, 25.2% in annually surveilled patients, and 12.2% in symptomatic patients (p<0.001). In a 10-year follow-up perspective, the median lead-time calculated for all surveilled patients was 6.5 months (7.2 for semiannual and 4.1 for annual surveillance). Lead-time bias accounted for most of the surveillance benefit until the third year of follow-up after HCC diagnosis. However, even after lead-time adjustment, semiannual surveillance maintained a survival benefit over symptomatic diagnosis (number of patients needed to screen = 13), as did annual surveillance (18 patients).

CONCLUSIONS

Lead-time bias is the main determinant of the short-term benefit provided by surveillance for HCC, but this benefit becomes factual in a long-term perspective, confirming the clinical utility of an anticipated diagnosis of HCC.

Cost-effectiveness of liver cancer screening in adults at high risk for liver cancer in the republic of Korea

PURPOSE

This study was conducted in order to determine the most cost-effective strategy, in terms of interval and age range, forliver cancer screening in the high-risk population of Korea.

MATERIALS AND METHODS

A stochastic modelwas used to simulate the cost-effectiveness ofliver cancer screening by combined ultrasonography and alpha-fetoprotein testing when varying both screening intervals and age ranges. The effectiveness of these screening strategies in the high-risk population was defined as the probability of detecting preclinical liver cancer, and costwas based on the direct cost ofthe screening and confirmative tests. Optimal cost-effectiveness was determined using the incremental cost-effectiveness ratio.

RESULTS

Among the 36 alternative strategies, one-year or two-year interval screening for men aged between 50 and 80 years, six-month or one-year interval screening for men aged between 40 and 80 years, and six-month interval screening for men aged between 30 and 80 years were identified as non-dominated strategies. For women, identified non-dominated strategies were: one-year interval screening between age 50 and 65 years, one-year or six-month interval screening between age 50 and 80 years, six-month interval screening between age 40 and 80 years, and six-month interval screening between age 30 and 80 years.

CONCLUSION

In Korea, a one-year screening interval for men aged 50 to 80 years would be marginally cost-effective. Further studies should be conducted in order to evaluate effectiveness of liver cancer screening, and compare the cost effectiveness of different liver cancer screening programs with a final outcome indicator such as qualityadjusted life-years or disability-adjusted life-years.

Analysis of inter-patient variations in tumour growth rate

Purpose

Inter-patient variations in tumour growth rate are usually interpreted as biological heterogeneity among patients due to, e.g., genetic variability. However, these variations might be a result of non-exponential, e.g. the Gompertzian, tumour growth kinetics. The aim was to study if the natural tumour growth deceleration, i.e. non-exponential growth, is a dominant factor in such variations.

Materials and methods

The correlation between specific growth rate (SGR) and the logarithm of tumour volume, Ln(V), was calculated for tumours in patients with meningioma, hepatocellular carcinoma, pancreatic carcinoma, primary lung cancer, post-chemotherapy regrowth of non-small cell lung cancer (NSCLC), and in nude mice transplanted with human midgut carcinoid GOT1, a tumour group which is biologically more homogeneous than patient groups.

Results

The correlation between SGR and Ln(V) was statistically significant for meningioma, post-chemotherapy regrowth of NSCLC, and the mouse model, but not for any other patient groups or subgroups, based on differentiation and clinical stage.

Conclusion

This method can be used to evaluate the homogeneity of tumour growth kinetics among patients. Homogeneity of post-chemotherapy regrowth pattern of NSCLC suggests that, in contrast to untreated tumours, the remaining resistant cells or stem cells (if exist) might have similar biological characteristics among these patients.

Role of endorectal MR imaging and MR spectroscopic imaging in defining treatable intraprostatic tumor foci in prostate cancer: quantitative analysis of imaging contour compared to whole-mount histopathology

PURPOSE

To investigate the role of endorectal MR imaging and MR spectroscopic imaging in defining the contour of treatable intraprostatic tumor foci in prostate cancer, since targeted therapy requires accurate target volume definition.

MATERIALS AND METHODS

We retrospectively identified 20 patients with prostate cancer who underwent endorectal MR imaging and MR spectroscopic imaging prior to radical prostatectomy and subsequent creation of detailed histopathological tumor maps from whole-mount step sections. Two experienced radiologists independently reviewed all MR images and electronically contoured all suspected treatable (≥0.5 cm(3)) tumor foci. Deformable co-registration in MATLAB was used to calculate the margin of error between imaging and histopathological contours at both capsular and non-capsular surfaces and the treatment margin required to ensure at least 95% tumor coverage.

RESULTS

Histopathology showed 17 treatable tumor foci in 16 patients, of which 8 were correctly identified by both readers and an additional 2 were correctly identified by reader 2. For all correctly identified lesions, both readers accurately identified that tumor contacted the prostatic capsule, with no error in contour identification. On the non-capsular border, the median distance between the imaging and histopathological contour was 1.4mm (range, 0-12). Expanding the contour by 5mm at the non-capsular margin included 95% of tumor volume not initially covered within the MR contour.

CONCLUSIONS

Endorectal MR imaging and MR spectroscopic imaging can be used to accurately contour treatable intraprostatic tumor foci; adequate tumor coverage is achieved by expanding the treatment contour at the non-capsular margin by 5mm.

Serological and histological indices of hepatocellular carcinoma and tumor volume doubling time

Hepatocellular carcinoma (HCC) frequently develops in cirrhotic liver and is one of the most common malignancies worldwide. The tumor volume doubling time (TVDT) reflects the natural tumor growth rate and is an indicator of the biological malignant potential of a tumor. The present study aimed to elucidate the association between the serological and histological indices of HCC and TVDT. TVDT was analyzed for 53 HCCs by measuring the enlargement of the tumor diameter on dynamic computed tomography. Differences in TVDT were compared among histological grades of HCC differentiation. The α-fetoprotein (AFP) doubling time (T2AFP) for 44 HCCs with AFP levels >200 ng/ml was calculated and the differences in T2AFP were compared according to the histological grade of HCC differentiation and positivity for Lens culinaris agglutinin-reactive fraction of α-fetoprotein (AFP-L3). Among these 44 HCCs, the correlation between T2AFP and TVDT was analyzed for the 27 tumors for which TVDT could be calculated. The mean ± standard deviation (SD) TVDT in Edmondson grade 1 (Ed1), Ed2 and Ed3 HCC was 138.3±110.3, 94.9±91.5 and 32.2±20.8 days, respectively (P<0.05). The mean ± SD T2AFP in Ed2 and Ed3 HCC was 121.0±167.5 and 37.3±24.6 days, respectively (P<0.01). TVDT and T2AFP decreased with histological dedifferentiation of HCC. The mean ± SD T2AFP in the AFP-L3-positive and -negative groups was 63.2±101.2 and 191.9±209.9 days, respectively, with a statistically significant difference between the groups (P<0.01). A significant correlation was observed between T2AFP and TVDT (correlation coefficient, 0.70; P<0.01). A significant correlation was also observed among TVDT, serological indices and histological grades of HCC differentiation. A short T2AFP and/or AFP-L3-positivity were shown to reflect a poorly differentiated HCC histopathology and a higher malignant potential.

Endorectal MRI and MR spectroscopic imaging of prostate cancer: developing selection criteria for MR-guided focal therapy

PURPOSE

To investigate criteria that can identify dominant treatable prostate cancer foci with high certainty at endorectal magnetic resonance imaging (MRI) and MR spectroscopic (MRS) imaging, and thus facilitate selection of patients who are radiological candidates for MR-guided focal therapy.

MATERIALS AND METHODS

We retrospectively identified 88 patients with biopsy-proven prostate cancer who underwent endorectal MRI and MRS imaging prior to radical prostatectomy with creation of histopathological tumor maps. Two independent readers noted the largest tumor foci at MRI, if visible, and the volume of concordant abnormal tissue at MRS imaging, if present. A logistic random intercept model was used to determine the association between clinical and MR findings and correct identification of treatable (over 0.5 cm3) dominant intraprostatic tumor foci.

RESULTS

Readers 1 and 2 identified dominant tumor foci in 50 (57%) and 58 (65%) of 88 patients; 42 (84%) and 48 (83%) of these were dominant treatable lesions at histopathology, respectively. Within the statistical model, the volume of concordant spectroscopic abnormality was the only factor that predicted correct identification of a dominant treatable lesion on T2-weighted images (odds ratio=1.75; 95% confidence interval=1.08 to 2.82; P value=0.02). In particular, all visible lesions on T2-weighted imaging associated with at least 0.54 cm3 of concordant spectroscopic abnormality were correctly identified dominant treatable tumor foci.

CONCLUSION

Patients with dominant intraprostatic tumor foci seen on T2-weighted MRI and associated with at least 0.54 cm3 of concordant MRS imaging abnormality may be radiological candidates for MR-guided focal therapy.

The usefulness of diffusion-weighted imaging in the characterization of liver lesions in patients with cirrhosis

AIM

To evaluate if diffusion-weighted imaging (DWI) is useful in characterizing liver lesions in patients with cirrhosis.

MATERIALS AND METHODS

A retrospective review revealed 37 patients with cirrhosis who had 41 histologically proven hepatocellular carcinoma (HCC) lesions. Another 20 patents with cirrhosis had 29 solid nodules that remained stable for at least 12 months and were deemed to be benign hepatic nodules (BHN). Of the HCC lesions, 14 were well-differentiated (WD HCC), 20 were moderately differentiated, and seven were poorly differentiated histology. For all lesions, two reviewers analysed signal characteristics and made apparent diffusion coefficient value (ADC) measurements.

RESULTS

Visual analysis of DWI was useful in that no HCC was hypointense and no BHN was hyperintense to liver. Visual analysis of DWI was not useful in separating WD HCC from higher grades. There was substantial overlap in ADC values of the HCC and BHN. Among HCC lesions, ADC values of more than 0.99 × 10(-3) mm(2)/s had sensitivity and specificity of 85% and 86% for reviewer 1, and 63% and 64% for reviewer 2 in diagnosing WD HCC.

CONCLUSIONS

ADC measurements of BHN were higher than that of HCC, and the ADC values of WD HCC were higher than that of more aggressive grades of HCC. However, quantitative measurements may not help in determining the histological grade of individual cases of HCC.

The impact of CT follow-up interval on stages of hepatocellular carcinomas detected during the surveillance of patients with liver cirrhosis

OBJECTIVE

The purpose of our study was to assess the relationship between time intervals of CT examinations and the stages of hepatocellular carcinomas (HCCs) detected during the surveillance of patients with liver cirrhosis.

MATERIALS AND METHODS

In this study, 73 patients with 93 HCCs (reference standard: surgery, n=7 [8 HCCs]; biopsy, n=2 [3 HCCs]; imaging criteria, n=64 [82 HCCs]) who showed no evidence of HCC on prior CT examinations were included. Patients were stratified into three groups based on the time interval between the two CT examinations: groups A (interval≤1 year, n=21), B (interval between 1 and 2 years, n=25), and C (interval≥2 years, n=27). Tumor stages according to the American Joint Committee on Cancer (AJCC), the Barcelona Clinic Liver Cancer (BCLC) staging system, and the Milan criteria were evaluated retrospectively by two reviewers. The Fisher exact test was used to compare tumor stages. Spearman correlation coefficients were used to assess the correlation between the CT interval and tumor size.

RESULTS

One (4%) HCC in group B and four (15%) HCCs in group C were larger than 5 cm in diameter, whereas no tumor was larger than 3 cm in diameter in group A. There was no difference in tumor diameter between groups, but tumor size was positively correlated with time interval between examinations (Spearman correlation coefficient, 0.472; p<0.001). In group A, 19 (90%) patients had cancers categorized as T1, and the remaining patients had cancers categorized as T2. In group B, one (4%) patient had a cancer that was categorized as T3b according to the AJCC classification, in the intermediate stage according to the BCLC classification, and above the Milan criteria. In group C, three (11%) patients had T3b cancers, and five had cancers in either intermediate or higher stage and above the Milan criteria.

CONCLUSION

HCC detected on CT performed within 1 year of a negative examination was at a curable stage in patients with liver cirrhosis.

Hepatocellular carcinoma presenting at contrast-enhanced multi-detector-row computed tomography or gadolinium-enhanced magnetic resonance imaging as a small (≤2 cm), indeterminate nodule: growth rate and optimal interval time for imaging follow-up

OBJECTIVE

The objective of the study was to measure growth rate and to determine the optimal interval time for imaging follow-up of hepatocellular carcinomas (HCCs) presenting at multi-detector-row computed tomography (MDCT) or magnetic resonance imaging (MRI) as small, indeterminate lesions.

METHODS

We included patients with cirrhosis with HCC initially presenting as indeterminate lesion of 2 cm or less at MDCT or MRI August 2005 to August 2009 and with available imaging follow-up. Measures of tumor growth included tumor volume doubling time (TVDT), tumor percentual diameter increase, and tumor percentual volume increase.

RESULTS

We examined 48 patients (mean age, 64 years) with 69 HCCs. At index examination, mean (SD) maximum transverse diameter and volume of lesions were 1.2 (SD, 0.3) cm and 0.6 (SD, 0.7) cm, respectively. Median TVDT was 210 days. Tumors with follow-up longer than 365 days had significant increase in tumor percentual diameter increase and tumor percentual volume increase.

CONCLUSIONS

Median TVDT of 210 days suggests extended follow-up of 6 months for small, indeterminate liver nodules detected at MDCT or MRI.

Preoperative tumor marker doubling time is a useful predictor of recurrence and prognosis after hepatic resection of hepatocellular carcinoma

BACKGROUND AND OBJECTIVES

It is important to identify prognostic factors in patients with hepatocellular carcinoma (HCC) before hepatectomy. No previous studies have addressed the predictive efficacy of the preoperative doubling times of alpha-fetoprotein (AFP) and protein induced by vitamin K absence (PIVKA-II).

METHODS

A total of 210 HCC patients who underwent a hepatic resection between 1998 and 2006 were prospectively evaluated. Serum AFP and PIVKA-II levels were measured at least twice before surgery to calculate the doubling times. Nineteen clinical factors that can be examined preoperatively, including the doubling times of AFP and PIVKA-II were investigated to identify prognostic factors for disease-free and overall survival after hepatectomy.

RESULTS

There was no relationship between preoperative levels and doubling times of AFP and PIVKA-II. In a multivariate analysis, patients with a doubling time of AFP ≤30 days and PIVKA-II ≤16 days showed a significantly worse disease-free (P = 0.02, P = 0.03, respectively) and overall survival (P < 0.0001, P = 0.03, respectively).

CONCLUSIONS

In HCC patients, the doubling times of preoperative serum AFP or PIVKA-II levels are useful tools to predict early postoperative recurrence and a poor prognosis.

Survival and cost-effectiveness analysis of competing strategies in the management of small hepatocellular carcinoma

The aim of the present study is to compare the survival rates and cost-effectiveness of different treatment strategies for small (<2 cm) hepatocellular carcinoma (HCC). Markov chains are developed to model different management strategies for patients with compensated cirrhosis and small HCC. Probabilities of progression and survival and the likelihood of orthotopic liver transplantation are taken from the literature and incorporated into the models. As a starting population, 1000 patients are followed over a period of 10 years. Patients treated immediately with transarterial chemoembolization (TACE) or radiofrequency ablation (RFA) live as long as or longer than patients who are monitored expectantly with the intention of liver transplantation once the HCC has grown larger than 2 cm and a higher transplant priority score becomes available. With TACE, immediate treatment results in an average survival time of 4.269 years versus 4.324 years with the monitoring strategy. With RFA, immediate treatment results in an average survival time of 5.273 years versus 5.236 years with the monitoring strategy. In addition, the cost analysis shows that immediate treatment with either TACE or RFA is less expensive than monitoring. The better cost-effectiveness of immediate therapy versus the monitoring strategy remains robust and unaffected by variations of the assumptions built into the model. In conclusion, in patients with compensated cirrhosis and small HCC, a strategy of immediate treatment with either TACE or RFA prevails over a strategy of expectant monitoring with the intention of transplantation.