Circulating Tumor DNA and Hepatocellular Carcinoma

Opportunities to address gaps in early detection and improve outcomes of liver cancer

Death rates from primary liver cancer (hepatocellular carcinoma [HCC]) have continued to rise in the United States over the recent decades despite the availability of an increasing range of treatment modalities, including new systemic therapies. Prognosis is strongly associated with tumor stage at diagnosis; however, most cases of HCC are diagnosed beyond an early stage. This lack of early detection has contributed to low survival rates. Professional society guidelines recommend semiannual ultrasound-based HCC screening for at-risk populations, yet HCC surveillance continues to be underused in clinical practice. On April 28, 2022, the Hepatitis B Foundation convened a workshop to discuss the most pressing challenges and barriers to early HCC detection and the need to better leverage existing and emerging tools and technologies that could improve HCC screening and early detection. In this commentary, we summarize technical, patient-level, provider-level, and system-level challenges and opportunities to improve processes and outcomes across the HCC screening continuum. We highlight promising approaches to HCC risk stratification and screening, including new biomarkers, advanced imaging incorporating artificial intelligence, and algorithms for risk stratification. Workshop participants emphasized that action to improve early detection and reduce HCC mortality is urgently needed, noting concern that many of the challenges we face today are the same or similar to those faced a decade ago and that HCC mortality rates have not meaningfully improved. Increasing the uptake of HCC screening was identified as a short-term priority while developing and validating better screening tests and risk-appropriate surveillance strategies.

Mutational and transcriptional alterations and clinicopathological factors predict the prognosis of stage I hepatocellular carcinoma

Background

The prognosis of hepatocellular carcinoma (HCC) has been extensively studied. However, the impact on prognosis of stage I HCC has not been well studied at clincopathological, mutational and transcriptional levels.

Methods

Here we first characterized the influencing factors of prognosis of stage I HCC patients by downloading and analyzing the whole-exome somatic mutation data, messenger ribonucleic acid (mRNA) transcription data, along with demographic and clinical information of 163 stage I HCC patients from the TCGA database. The relationship between the influencing factors and HCC prognosis was studied in detail, and a prediction Nomogram model was established. Figures and tables were plotted using the R software.

Results

TP53, CTNNB1, TTN, MUC16 and ALB were the top mutated genes in stage I HCC. A series of co-mutations and mutually exclusive mutations were identified. Twenty-nine genes with significant stratification on prognosis were identified, including highly mutated LRP1B, ARID1A and PTPRQ. Patients with wild type (WT) genes unanimously exhibited significantly better overall survival rate than those with mutants. Patients with the top 10% tumor mutational burden (TMB) exhibited significantly worse prognosis than the rest 90%. Further characterization of transcriptional profile revealed that membrane functions, cell skeleton proteins, ion channels, receptor function and cell cycle were comprehensively altered in stage I HCC. Univariate and multivariate analyses were performed at clinicopathological, mutational and transcriptional levels. The combined analysis revealed sex, race, TMB, neoplasm histologic grade, Child–Pugh grade, MMRN1, OXT and COX6A2 transcription as independent risk factors. These factors were used to establish a Nomogram model to predict the prognosis of individual HCC patients.

Conclusions

The influencing factors of prognosis of stage I HCC have been characterized for the first time at clinicopathological, mutational and transcriptional levels. A Nomogram model has been established to predict the prognosis. Further validation is needed to confirm the effectiveness and reliability of the model.

Changing epidemiology of hepatocellular carcinoma in Asia

Liver cancer is the fifth most common cancer and the second leading cause of malignant death in Asia, and Asia reports 72.5% of the world's cases in 2020. As the most common histological type, hepatocellular carcinoma (HCC) accounts for the majority of incidence and mortality of liver cancer cases. This review presents the changing epidemiology of HCC in Asian countries in recent years. Globally, aged, male and Asian populations remain the group with the highest risk of HCC. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are still the leading risk factors of HCC with a slight decline in most Asian countries, which is mainly attributed to HBV vaccination of newborns, prevention of HCV horizontal transmission and treatment of chronic hepatitis. However, the prevalence of HCC caused by metabolic factors, including metabolic syndrome, obesity and non-alcoholic fatty liver diseases, is increasing rapidly in Asian countries, which may eventually become the major cause of HCC. Excessive alcohol consumption continues to be an important risk factor as the average consumption of alcohol is still growing. Hopefully, great effort has been made to better prevention and treatment of HCC in most Asian regions, which significantly prolongs the survival of HCC patients. Asian countries tend to use more aggressive intervention than European and American countries, but it remains unclear whether this preference is related to a better prognosis. In conclusion, HCC remains a major disease burden in Asia, and the management of HCC should be adjusted dynamically based on the changing epidemiology.

Liquid Biopsy Using Cell-Free or Circulating Tumor DNA in the Management of Hepatocellular Carcinoma

Liver cancer (hepatocellular carcinoma [HCC]) is a fatal cancer worldwide and often is detected at an advanced stage when treatment options are very limited. This drives the development of techniques and platforms for early detection of HCC. In recent years, liquid biopsy has provided a means of noninvasive detection of cancers. By detecting plasma circulating tumor DNA (ctDNA) released from dying cancer cells, the presence of HCC can be detected in a noninvasive manner. In this review, we discuss the molecular characteristics of ctDNA and its various molecular landscapes in HCC. These include the mutational landscape, single-nucleotide variations, copy number variations, methylation landscape, end motif/coordinate preference, hepatitis B virus integration, and mitochondrial DNA mutations. The consistency between the plasma ctDNA and the tumor tissue genomic DNA mutational profile is pivotal for the clinical utility of ctDNA in the clinical management of HCC. With strategic use of genetic information provided from plasma ctDNA profiling and procedure standardization to facilitate implementation in clinical practice, better clinical management would become permissible through more efficient detection and diagnosis of HCC, better prognostication, precision-matched treatment guidance, and more reliable disease monitoring.

Cancer Genomic Alterations Can Be Potential Biomarkers Predicting Microvascular Invasion and Early Recurrence of Hepatocellular Carcinoma

Background

High recurrence incidence and poor survival after hepatectomy are enormous threats to hepatocellular carcinoma (HCC) patients, which can be caused by microvascular invasion (MVI). However, it is difficult to predict preoperative MVI status. In this study, we focus on cancer genomic alterations to comprehensively explore potential MVI and early recurrence biomarkers and provide clues to the mechanisms of HCC invasion and metastasis.

Methods

Forty-one patients with initially suspected HCC who were undergoing hepatectomy were finally enrolled. High-throughput targeted sequencing was performed on genomic alterations in their preoperative plasma and surgical fresh tumor tissues utilizing the 1,021-gene panel.

Results

HCC patients without MVI had longer RFS than MVI ones (p < 0.0001). The mutant incidence of genes like KEAP1, TP53, HIST1H3D, NFKBIA, PIK3CB, and WRN was higher in both MVI and early-recurrence patients than their counterparts. Besides, the alteration rates of Rap1 and Ras signaling pathways were significantly higher in MVI patients than NMVI ones (p < 0.05), and a similar trend of differences was also found in early-recurrence/non-recurrence comparison. The maximal variant allele frequency (VAF) of circulating tumor DNA (ctDNA) was statistically higher in MVI patients than NMVI ones (0.038 vs. 0.012, p = 0.0048). With the cutoff value of 0.018, ctDNA maximal VAF could potentially predict the presence of MVI with an AUC of 0.85 (95% CI 0.693–0.998, p = 0.0062).

Conclusion

The integration of a panel containing specific mutated genes and ctDNA maximal VAF for predicting MVI and early recurrence of HCC may achieve better performance.

A Genome-Wide Investigation of Effects of Aberrant DNA Methylation on the Usage of Alternative Promoters in Hepatocellular Carcinoma

BACKGROUND

The alternative usage of promoters provides a way to regulate gene expression, has a significant influence on the transcriptome, and contributes to the cellular transformation of cancer. However, the function of alternative promoters (APs) in hepatocellular carcinoma (HCC) has not been systematically studied yet. In addition, the potential mechanism of regulation to the usage of APs remains unclear. DNA methylation, one of the most aberrant epigenetic modifications in cancers, is known to regulate transcriptional activity. Whether DNA methylation regulates the usage of APs needs to be explored. Here, we aim to investigate the effects of DNA methylation on usage of APs in HCC.

METHODS

Promoter activities were calculated based on RNA-seq data. Functional enrichment analysis was implemented to conduct GO terms. Correlation tests were used to detect the correlation between promoter activity and methylation status. The LASSO regression model was used to generate a diagnostic model. Kaplan-Meier analysis was used to compare the overall survival between high and low methylation groups. RNA-seq and whole-genome bisulfite sequencing (WGBS) in HCC samples were performed to validate the correlation of promoter activity and methylation.

RESULTS

We identified 855 APs in total, which could be well used to distinguish cancer from normal samples. The correlation of promoter activity and DNA methylation in APs was observed, and the APs with negative correlation were defined as methylation-regulated APs (mrAPs). Six mrAPs were identified to generate a diagnostic model with good performance (AUC = 0.97). Notably, the majority of mrAPs had CpG sites that could be used to predict clinical outcomes by methylation status. Finally, we verified 85.6% of promoter activity variation and 92.3% of methylation changes in our paired RNA-seq and WGBS samples, respectively. The negative correlation between promoter activity and methylation status was further confirmed in our HCC samples.

CONCLUSION

The aberrant methylation status plays a critical role in the precision usage of APs in HCC, which sheds light on the mechanism of cancer development and provides a new insight into cancer screening and treatment.

Serial circulating tumor DNA to predict early recurrence in patients with hepatocellular carcinoma: a prospective study

We studied the value of circulating tumor DNA (ctDNA) in predicting early postoperative tumor recurrence and monitoring tumor burden in patients with hepatocellular carcinoma (HCC). Plasma-free DNA, germline DNA, and tissue DNA were isolated from 41 patients with HCC. Serial ctDNAs were analyzed by next-generation sequencing before and after operation. Whole-exome sequencing was used to detect the DNA of HCC and adjacent tissues. In total, 47 gene mutations were identified in the ctDNA of the 41 patients analyzed before surgery. ctDNA was detected in 63.4% and 46% of the patient plasma pre- and postoperation, respectively. The preoperative ctDNA positivity rate was significantly lower in the nonrecurrence group than in the recurrence group. With a median follow-up of 17.7 months, nine patients (22%) experienced tumor recurrence. ctDNA positivity at two time-points was associated with significantly shorter recurrence-free survival (RFS). Tumors with NRAS, NEF2L2, and MET mutations had significantly shorter times to recurrence than those without mutations and showed high recurrence prediction performance by machine learning. Multivariate analyses showed that the median variant allele frequency (VAF) of mutations in preoperative ctDNA was a strong independent predictor of RFS. ctDNA is a real-time monitoring indicator that can accurately reflect tumor burden. The median VAF of baseline ctDNA is a strong independent predictor of RFS in individuals with HCC.

PRCC reduces the sensitivity of cancer cells to DNA damage by inhibiting JNK and ATM/ATR pathways and results in a poor prognosis in hepatocellular carcinoma

Background and aim

The proline rich mitotic checkpoint control factor (PRCC) is involved in the splicing process of pre-mRNA. This study aims to elucidate PRCC molecular function, regulatory mechanism and diagnostic value in hepatocellular carcinoma (HCC).

Methods

The tissue microarray and serum samples from HCC patients were used to investigate the clinical value of PRCC. The biological function and molecular mechanism of PRCC were demonstrated by cell biology, biochemical and animal experiments. The relationship between PRCC and intratumoral heterogeneity (ITH) was analyzed by bioinformatics.

Results

PRCC was highly expressed in HCC tissues and related to the poor prognosis of HCC patients, its contents were elevated in the preoperative sera of HCC patients. PRCC exhibited high application potential as a substitute or adjuvant of alpha-fetoprotein (AFP) for clinical diagnosis of HCC. It had no significant effect on the proliferation of cancer cells, but could inhibit spheroid formation and metastasis of HCC cells in vitro and in vivo. The high ectopic expression of PRCC made cancer cells insensitive to DNA damage, and enhanced the heterogeneity of HCC cells by inhibiting the JNK/ATM/ATR/ATF2 axis. The HCC patients with high PRCC expression had high ITH, which corresponded to a short overall survival in patients.

Conclusions

PRCC has high application potential as a substitute or adjuvant of AFP for clinical diagnosis of HCC. The high ectopic expression of PRCC not only caused HCC cells to resist to cell death induced by DNA damage, but also endowed cancer cells with numerous DNA mutations to become increasingly heterogeneous, finally leading to a poor prognosis in HCC patients. These data suggested PRCC could be a promising therapeutic target in HCC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00699-x.

Clinical Application Value of Circulating Cell-free DNA in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and a leading cause of cancer-related deaths. Due to late diagnosis, early intrahepatic metastasis and nonresponse to systemic treatments, surgical resection and/or biopsy specimens remain the gold standard for disease staging, grading and clinical decision-making. Since only a small amount of tissue was obtained in a needle biopsy, the conventional tissue biopsy is unable to represent tumor heterogeneity in HCC. For this reason, it is imperative to find a new non-invasive and easily available diagnostic tool to detect HCC at an early stage and to monitor HCC recurrence. The past decade has witnessed considerable evolution in the development of liquid biopsy technologies with the emergence of next-generation sequencing. As a liquid biopsy approach, molecular analysis of cell-free DNA (cfDNA), characterized by noninvasiveness and real-time analysis, may accurately represent the tumor burden and comprehensively reflect genetic profile of HCC. Therefore, cfDNA may be used clinically as a predictive biomarker in early diagnosis, outcome assessment, and even molecular typing. In this review, we provide an update on the recent advances made in clinical applications of cfDNA in HCC.

Identification of Gene Signature as Diagnostic and Prognostic Blood Biomarker for Early Hepatocellular Carcinoma Using Integrated Cross-Species Transcriptomic and Network Analyses

Background: Hepatocellular carcinoma (HCC) is considered the most common type of liver cancer and the fourth leading cause of cancer-related deaths in the world. Since the disease is usually diagnosed at advanced stages, it has poor prognosis. Therefore, reliable biomarkers are urgently needed for early diagnosis and prognostic assessment. Methods: We used genome-wide gene expression profiling datasets from human and rat early HCC (eHCC) samples to perform integrated genomic and network-based analyses, and discovered gene markers that are expressed in blood and conserved in both species. We then used independent gene expression profiling datasets for peripheral blood mononuclear cells (PBMCs) for eHCC patients and from The Cancer Genome Atlas (TCGA) database to estimate the diagnostic and prognostic performance of the identified gene signature. Furthermore, we performed functional enrichment, interaction networks and pathway analyses. Results: We identified 41 significant genes that are expressed in blood and conserved across species in eHCC. We used comprehensive clinical data from over 600 patients with HCC to verify the diagnostic and prognostic value of 41-gene-signature. We developed a prognostic model and a risk score using the 41-geneset that showed that a high prognostic index is linked to a worse disease outcome. Furthermore, our 41-gene signature predicted disease outcome independently of other clinical factors in multivariate regression analysis. Our data reveals a number of cancer-related pathways and hub genes, including EIF4E, H2AFX, CREB1, GSK3B, TGFBR1, and CCNA2, that may be essential for eHCC progression and confirm our gene signature's ability to detect the disease in its early stages in patients' biological fluids instead of invasive procedures and its prognostic potential. Conclusion: Our findings indicate that integrated cross-species genomic and network analysis may provide reliable markers that are associated with eHCC that may lead to better diagnosis, prognosis, and treatment options.

Multiple-level copy number variations in cell-free DNA for prognostic prediction of HCC with radical treatments

Copy number variations (CNVs) in cell-free DNA (cfDNA) are emerging as noninvasive biomarkers for various cancers. However, multiple-level analysis of cfDNA CNVs for hepatocellular carcinoma (HCC) patients with radical treatments remains uninvestigated. Here, CNVs at genome-wide, chromosomal-arm, and bin levels were analyzed in cfDNA from 117 HCC patients receiving radical treatments. Then, the relationship between cfDNA CNVs and clinical outcomes was explored. Our results showed that a concordant profile of CNVs was observed between cfDNA and tumor tissue DNA. Three genome-wide CNV indicators including tumor fraction (TFx), prediction score (P-score), and stability score (S-score) were calculated and demonstrated to exhibit significant correlation with poorer overall survival (OS) and recurrence-free survival (RFS). Furthermore, the high-frequency cfDNA CNVs at chromosomal-arm level including the loss of 4q, 17p, and 19p and the gain of 8q and 1q clearly predicted HCC prognosis. Finally, a bin-level risk score was constructed to improve the ability of CNVs in predicting prognosis. Altogether, our study indicates that the multiple-level cfDNA CNVs are significantly associated with OS and RFS in HCC patients with radical treatments, suggesting that cfDNA CNVs detected by low-coverage whole-genome sequencing (WGS) may be used as potential prognostic biomarkers of HCC patients.

Evolving Treatment of Advanced Hepatocellular Carcinoma in the Asia-Pacific Region: A Review and Multidisciplinary Expert Opinion

Simple Summary

For years, the systemic therapies sorafenib and lenvatinib have represented standard of care for first-line treatment of advanced hepatocellular carcinoma (HCC). The recent approval of atezolizumab in combination with bevacizumab heralded the arrival of immunotherapy for first-line treatment of advanced HCC, and the field is growing, with other combination immunotherapies under investigation. Focusing on the Asia–Pacific region, where drug availability and reimbursement systems differ widely, this article reviews the evolving treatment landscape and summarises the authors’ expert opinion on therapeutic decision-making to optimise outcomes in advanced HCC.

Abstract

Hepatocellular carcinoma (HCC) is the fourth most common driver of cancer-related death globally, with an estimated 72% of cases in Asia. For more than a decade, first-line systemic treatments for advanced or unresectable HCC were limited to the multi-targeted kinase inhibitors sorafenib and, more recently, lenvatinib. Now, treatment options have expanded to include immunotherapy, as exemplified by the immune checkpoint inhibitor (ICI) atezolizumab combined with the antiangiogenic agent bevacizumab. Additional combinations of ICIs with kinase inhibitors, other ICIs, or antiangiogenic agents are under investigation, further supporting the new era of immunotherapy for first-line treatment of advanced or unresectable HCC. We describe this evolving landscape and provide expert opinion on therapeutic best practices in the Asia–Pacific region, where different costs of, and patient access to, treatment are a challenge. With the combination of atezolizumab plus bevacizumab likely to become the clinical standard of care, optimising treatment sequence and ensuring patient access to newer therapies remain priorities. Cost containment and treatment sequencing may be facilitated by characterisation of predictive positive and negative biomarkers. With these considerations in mind, this review and expert opinion focused on advanced HCC in the Asia–Pacific region offers perspectives of multiple stakeholders, including physicians, payer systems, and patients.

Current status of ctDNA in precision oncology for hepatocellular carcinoma

The conventional method used to obtain a tumor biopsy for hepatocellular carcinoma (HCC) is invasive and does not evaluate dynamic cancer progression or assess tumor heterogeneity. It is thus imperative to create a novel non-invasive diagnostic technique for improvement in cancer screening, diagnosis, treatment selection, response assessment, and predicting prognosis for HCC. Circulating tumor DNA (ctDNA) is a non-invasive liquid biopsy method that reveals cancer-specific genetic and epigenetic aberrations. Owing to the development of technology in next-generation sequencing and PCR-based assays, the detection and quantification of ctDNA have greatly improved. In this publication, we provide an overview of current technologies used to detect ctDNA, the ctDNA markers utilized, and recent advances regarding the multiple clinical applications in the field of precision medicine for HCC.

Epigenetic Biomarkers for the Diagnosis and Treatment of Liver Disease

Research in the last decades has demonstrated the relevance of epigenetics in controlling gene expression to maintain cell homeostasis, and the important role played by epigenome alterations in disease development. Moreover, the reversibility of epigenetic marks can be harnessed as a therapeutic strategy, and epigenetic marks can be used as diagnosis biomarkers. Epigenetic alterations in DNA methylation, histone post-translational modifications (PTMs), and non-coding RNA (ncRNA) expression have been associated with the process of hepatocarcinogenesis. Here, we summarize epigenetic alterations involved in the pathogenesis of chronic liver disease (CLD), particularly focusing on DNA methylation. We also discuss their utility as epigenetic biomarkers in liquid biopsy for the diagnosis and prognosis of hepatocellular carcinoma (HCC). Finally, we discuss the potential of epigenetic therapeutic strategies for HCC treatment.

Cellular heterogeneity and plasticity in liver cancer

Hepatocarcinogenesis involves complex genetic and cellular dysregulations which drive the formation of hepatocellular carcinoma (HCC), the predominant form of primary liver cancer, with extensive heterogeneity. In contrast to the broad spectrum of molecularly driven therapies available for defined patient groups in certain cancer types, unfortunately the treatment options for HCC are highly limited. The lack of representative molecular and cellular signatures in the heterogeneous HCC tumors that can effectively guide the choice of the most appropriate treatment among the patients unavoidably limits the treatment outcome. Advancement and wide availability of the next-generation sequencing technologies have empowered us to examine and capture not only the detailed genetic alterations of the HCC cells but also the precise composition of different cell types within the tumor microenvironment and their interactions with the HCC cells at an unprecedented level. The information generated has provided new insight and better defined the inter-patient intertumoral heterogeneity, intra-patient intratumoral heterogeneity as well as the plasticity of HCC cells. These collectively provide a robust scientific basis in guiding the development and use of targeted therapy and immunotherapy. To complement, liquid biopsy coupled with high-sensitivity sequencing could potentially be adopted as a more practical and safer approach to detect and reflect the tumor heterogeneity in HCC patients in guiding the choice of treatment and monitoring disease progression.

Circulating Cell-Free DNA Combined to Magnetic Resonance Imaging for Early Detection of HCC in Patients with Liver Cirrhosis

Simple Summary

Liver cirrhosis can develop into malignant disease over time. Frequent monitoring would be advisable to detect the earliest signs of HCC progress resulting in a possible earlier treatment of the patient. Our study showed that the combination of genetic analysis of DNA freely circulating in the blood of the cirrhotic patients with MRI can represent a powerful strategy to timely identify suspect lesions, which can then be followed up more closely and thus potentially be treated earlier. In this way, personalized medicine can be applied to liver diseases such as cirrhosis.

Abstract

Liquid biopsy based on circulating cell-free DNA (cfDNA) is a promising non-invasive tool for the prognosis of hepatocellular cancer (HCC). In this exploratory study we investigated whether cfDNA and gene variants associated with HCC may be found in patients with liver cirrhosis (LC) and thus identify those at an increased risk for HCC. A cohort of 40 LC patients with no suspect neoplastic lesions was included in this study. Next generation sequencing (NGS) of cfDNA isolated from plasma was performed on a panel of 597 selected genes. Images of the patients who underwent MRI with hepatospecific contrast media during the study period were retrospectively re-evaluated (imaging was not part of the prospective study). cfDNA was detected in the plasma of 36 patients with LC. NGS-based analyses identified 20 variants in different combinations. Re-evaluation of the MRI images that were available for a proportion of the patients (n = 27) confirmed the absence of lesions in 8 cases carrying cfDNA without variants. In 6 of 19 patients with identified variants and MRI images available, MRI revealed a precursor lesion compatible with HCC and new lesions were discovered at follow-up in two patients. These precursor lesions were amenable for curative treatments. Mutation analysis revealed selective HCC related gene mutations in a subset of patients with LC, raising the suspect that these patients were at an increased risk for HCC development. MRI findings confirmed suspect nodular lesions of early stage HCC not detected with current standard screening procedures, which were only seen in patients carrying cfDNA variants. This opens a perspective for an HCC screening strategy combining both liquid biopsy and MRI in patients with LC.

The prognostic value of postoperative circulating cell-free DNA in operable hepatocellular carcinoma

BACKGROUND

Tumor biomarkers are eagerly needed in monitoring the recurrence of operable hepatocellular carcinoma (HCC). Circulating cell-free DNA (cfDNA) is a promising noninvasive molecular biomarker for HCC. The current study aimed to evaluate the clinical significance of the postoperative cfDNA in operable HCC.

METHODS

This study enrolled 82 HCC patients from January 2018 to June 2019. All patients underwent liver surgery and were pathologically diagnosed with HCC. Postoperative blood samples were collected from each patient. A fluorometric dsDNA assay was used to measure the concentration of cfDNA. We explore the correlation between cfDNA and recurrence. Kaplan-Meier's curves were used to evaluate the recurrence-free survival (RFS). Univariate and multivariate Cox regression analyses were used for assessing the relative clinical variables in predicting recurrence.

RESULTS

Of the 82 HCC patients, 72 (87%) patients are male and the average age was 52.7 ± 12.8 years. The cfDNA-low and cfDNA-high groups had median recurrence times of 19.5 months and 14.0 months, respectively (p = .023). Multivariate analysis showed that postoperative cfDNA, tumour number and microvascular invasion (p < .050) were independent risk factors for recurrence in operable HCC.

CONCLUSIONS

Postoperative cfDNA is still a promising marker to predict prognosis in postoperative HCC patients although prospective and large multicenter clinical study is needed to further validate the relationship between cfDNA and HCC recurrence.

New advances in the diagnosis and management of hepatocellular carcinoma

Hepatocellular carcinoma is one of the leading causes of cancer related death in the world. Biannual surveillance for the disease in patients with cirrhosis and in high risk carriers of hepatitis B virus allows early stage cancer detection and treatment with good long term outcomes. Liver ultrasonography and serum α fetoprotein are the most commonly used surveillance tests. If suspicious results are found on the surveillance test, multiphasic computed tomography or magnetic resonance imaging should be undertaken to confirm the diagnosis of hepatocellular carcinoma. If radiologic tests show inconclusive results, liver biopsy or repeat imaging could be considered for confirmation of hepatocellular carcinoma. Management of the disease is complex. Patients should be evaluated by a multidisciplinary team, and the selection of treatment should consider factors such as tumor burden, severity of liver dysfunction, medical comorbidities, local expertise, and preference of patients. Early stage hepatocellular carcinoma is best managed by curative treatment, which includes resection, ablation, or transplantation. Patients with intermediate stage disease often receive locoregional treatment. Systemic treatment is reserved for patients with advanced disease. Several positive, phase III, randomized controlled trials have expanded the systemic treatment options for advanced hepatocellular carcinoma with promising long term outcomes, especially trials using combination treatments, which could also have eventual implications for the treatment of earlier stage disease.

Progression and dormancy in metastatic thyroid cancer: concepts and clinical implications

Distant metastasis classically has been defined as a late-stage event in cancer progression. However, it has become clear that metastases also may occur early in the "lifetime" of a cancer and that they may remain stable at distant sites. This stability of metastatic cancer deposits has been termed "metastatic dormancy" or, as we term it, "metastatic progression dormancy" as the progression either may reflect growth of already existing metastases or new cancer spread. Biologically, dormancy is the presence of nongrowing, static metastatic cells that survive over time. Clinically, dormancy is defined by stability in tumor markers, imaging, and clinical course. Metastatic well-differentiated thyroid cancer offers an excellent tumor type to understand these processes for several reasons: (1) primary therapy often includes removal of the entire gland with ablation of residual normal tissue thereby removing one source for new metastases; (2) the presence of a sensitive biochemical and radiographic monitoring tests enabling monitoring of metastasis throughout the progression process; and (3) its tendency toward prolonged clinical dormancy that can last for years or decades be followed by progression. This latter factor provides opportunities to define therapeutic targets and/or markers of progression. In this review, we will discuss concepts of metastatic progression dormancy and the factors that drive both long-term stability and loss of dormancy with a focus on thyroid cancer.

Biomarkers in Hepatocellular Carcinoma: Diagnosis, Prognosis and Treatment Response Assessment

Hepatocellular carcinoma (HCC) is one of the main cancer-related causes of death worldwide. Thus, there is a constant search for improvement in screening, diagnosis, and treatment strategies to improve the prognosis of this malignancy. The identification of useful biomarkers for surveillance and early HCC diagnosis is still deficient, with available serum biomarkers showing low sensitivity and heterogeneous specificity despite different cut-off points, even when assessed longitudinally, or with a combination of serum biomarkers. In contrast, HCC biomarkers used for prognostic (when associated with clinical outcomes) or predictive purposes (when associated with treatment response) may have an increased clinical role in the near future. Furthermore, some serum biomarkers are already implicated as a treatment selection tool, whether to provide access to certain therapies or to assess clinical benefit after treatment. In the present review we will discuss the clinical utility and foreseen future of HCC biomarkers implicated in surveillance, diagnosis, prognosis, and post-treatment assessment.