Circulating tumor cells in the central and peripheral venous compartment - assessing hematogenous dissemination after transarterial chemoembolization of hepatocellular carcinoma

Investigating the Influence of Preoperative Trans Arterial Embolization (TAE) and Predictive Potential of Circulating Tumor Cells (CTCs) in Prognosis of Hepatocellular Carcinoma

Introduction

Circulating tumor cells are a promising biomarker in many malignancies. CTC dissemination during the operative procedure can lead to disease recurrence. The effect of preoperative transarterial embolization on the release of CTCs and miRNA panels and oncological outcomes in large hepatocellular carcinomas has been evaluated.

Materials and methods

The study included non-metastatic HCC >5 cm in size, that were completely resected after TAE (n = 10). Blood was collected pre-TAE, post-TAE, postoperative (day 2,30 and 180) and analyzed for the presence of CTC and miRNA (miR-885-5p, miR-22-3p, miR-642b-5p). The samples were subjected to CTC enrichment, isolation and staining using the markers CD45, EpCAM, and cytokeratin (CK). The data was analyzed using Gene Expression Suite software.

Results

The CTC enumeration resulted in three groups: Group 1- CTC present at both pre-TAE and postoperative day 30 (n = 4), Group 2- CTC present at pre-TAE and clearing at postoperative day 30 (n = 2), Group 3- No CTC detected at any stages (n = 3). Group 2 patients had better survival compared with the other groups. Downregulation of miRNA 22-3p also had favorable prognostic implications.

Conclusion

Although preoperative TAE does not seem to impact CTC shedding, CTC clearance may prove to be a valuable biomarker in prognosticating HCC. A larger study to evaluate the significance of CTCs as a prognostic marker is warranted to further evaluate these findings.

Prospects of liquid biopsy in the prognosis and clinical management of gastrointestinal cancers

Gastrointestinal (GI) cancers account for one-fourth of the global cancer incidence and are incriminated to cause one-third of cancer-related deaths. GI cancer includes esophageal, gastric, liver, pancreatic, and colorectal cancers, mostly diagnosed at advanced stages due to a lack of accurate markers for early stages. The invasiveness of diagnostic methods like colonoscopy for solid biopsy reduces patient compliance as it cannot be frequently used to screen patients. Therefore, minimally invasive approaches like liquid biopsy may be explored for screening and early identification of gastrointestinal cancers. Liquid biopsy involves the qualitative and quantitative determination of certain cancer-specific biomarkers in body fluids such as blood, serum, saliva, and urine to predict disease progression, therapeutic tolerance, toxicities, and recurrence by evaluating minimal residual disease and its correlation with other clinical features. In this review, we deliberate upon various tumor-specific cellular and molecular entities such as circulating tumor cells (CTCs), tumor-educated platelets (TEPs), circulating tumor DNA (ctDNA), cell-free DNA (cfDNA), exosomes, and exosome-derived biomolecules and cite recent advances pertaining to their use in predicting disease progression, therapy response, or risk of relapse. We also discuss the technical challenges associated with translating liquid biopsy into clinical settings for various clinical applications in gastrointestinal cancers.

Liquid Biopsy in Hepatocellular Carcinoma: The Significance of Circulating Tumor Cells in Diagnosis, Prognosis, and Treatment Monitoring

Hepatocellular carcinoma (HCC) is an aggressive malignancy with poor outcomes when diagnosed at an advanced stage. Current curative treatments are most effective in early-stage HCC, highlighting the importance of early diagnosis and intervention. However, existing diagnostic methods, such as radiological imaging, alpha-fetoprotein (AFP) testing, and biopsy, have limitations that hinder early diagnosis. AFP elevation is absent in a significant portion of tumors, and imaging may have low sensitivity for smaller tumors or in the presence of cirrhosis. Additionally, as our understanding of the molecular pathogenesis of HCC grows, there is an increasing need for molecular information about the tumors. Biopsy, although informative, is invasive and may not always be feasible depending on tumor location. In this context, liquid biopsy technology has emerged as a promising approach for early diagnosis, enabling molecular characterization and genetic profiling of tumors. This technique involves analyzing circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), or tumor-derived exosomes. CTCs are cancer cells shed from the primary tumor or metastatic sites and circulate in the bloodstream. Their presence not only allows for early detection but also provides insights into tumor metastasis and recurrence. By detecting CTCs in peripheral blood, real-time tumor-related information at the DNA, RNA, and protein levels can be obtained. This article provides an overview of CTCs and explores their clinical significance for early detection, prognosis, treatment selection, and monitoring treatment response in HCC, citing relevant literature.

Enumeration and Characterization of Circulating Tumor Cells in Patients with Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization

Circulating tumor cells (CTCs), and particularly circulating cancer stem cells (cCSC), are prognostic biomarkers for different malignancies and may be detected using liquid biopsies. The ex vivo culture of cCSCs would provide valuable information regarding biological aggressiveness and would allow monitoring the adaptive changes acquired by the tumor in real time. In this prospective pilot study, we analyzed the presence of EpCAM⁺ CTCs using the IsoFlux system in the peripheral blood of 37 patients with hepatocellular carcinoma undergoing transarterial chemoembolization (TACE). The average patient age was 63.5 ± 7.9 years and 91.9% of the patients were men. All patients had detectable CTCs at baseline and 20 patients (54.1%) showed CTC aggregates or clusters in their peripheral blood. The increased total tumor diameter (OR: 2.5 (95% CI: 1.3-4.8), p = 0.006) and the absence of clusters of CTCs at baseline (OR: 0.2 (95% CI: 0.0-1.0), p = 0.049) were independent predictors of a diminished response to TACE. Culture of cCSC was successful in five out of thirty-three patients, mostly using negative enrichment of CD45^- cells, ultra-low adherence, high glucose, and a short period of hypoxia followed by normoxia. In conclusion, the identification of clusters of CTCs before TACE and the implementation of standardized approaches for cCSC culture could aid to predict outcomes and to define the optimal adjuvant therapeutic strategy for a true personalized medicine in hepatocellular carcinoma.

Technologies for Viable Circulating Tumor Cell Isolation

The spread of tumor cells throughout the body by traveling through the bloodstream is a critical step in metastasis, which continues to be the main cause of cancer-related death. The detection and analysis of circulating tumor cells (CTCs) is important for understanding the biology of metastasis and the development of antimetastatic therapy. However, the isolation of CTCs is challenging due to their high heterogeneity and low representation in the bloodstream. Different isolation methods have been suggested, but most of them lead to CTC damage. However, viable CTCs are an effective source for developing preclinical models to perform drug screening and model the metastatic cascade. In this review, we summarize the available literature on methods for isolating viable CTCs based on different properties of cells. Particular attention is paid to the importance of in vitro and in vivo models obtained from CTCs. Finally, we emphasize the current limitations in CTC isolation and suggest potential solutions to overcome them.

Circulating tumor cells as a preoperative risk marker for occult metastases in patients with resectable cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive tumor associated with a high rate of recurrence after resection. An important risk factor for recurrence is the presence of occult metasta-ses, which are not radiologically detectable at the time of diagnosis. There are currently no biomarkers for the preoperative assessment of micrometastases. A previous study demonstrated the prognostic relevance of circulating tumor cells (CTC) in patients with advanced CCA but the potential of CTCs as a preoperative marker for detecting occult metastases has not been investigated so far. In this two-phase study, we first recruited a cohort of 27 patients with histologically proven, metastatic CCA or gallbladder cancer (GBCA) to assess feasibility (feasibility cohort, FC). CTCs were measured in the peripheral blood using the CellSearch System (CSS) between October 2012 and January 2017. Subsequently, in 11 patients undergoing curative-intended resection for CCA (intrahepatic CCA: n =4; extrahepatic CCA n= 6; gallbladder cancer: n=1), peripheral and central venous blood specimens were obtained to improve detection rate by simultaneous measurement and to elucidate distribution of CTCs in different venous compartments. Presence of CTCs detection was correlated with postoperative TNM-status.

In the FC, CTCs (range 1-3 cells, median: 1) were detected in 40% (11/27) patients and were signifi-cantly associated with worse overall survival (hazard ratio: 3.59; 95% CI: 1.79- 7.1; p = 0.04). By combined peripheral and central measurement, CTC detection was increased to 54% (6/11) in the resection cohort (RC) and was associated with metastases that were only identified during the surgical procedure (peritoneal carcinoma: n = 1; infiltration of the duodenum: n = 1) or immediately after surgery (evidence of pulmonary metastases by CT scan two days after resection, not evident on initial tumor staging prior resection). Taken together, in this single center pilot study, we demonstrated that CTCs are detectable in CCA patients and are associated with significantly impaired survival in patients at metastatic stage. Detection rate prior to surgery was improved to >50% by combined peripheral and central measurement. Moreover, preoperative CTC detection may indicate existing metastases and could help to stratify patients more accurately.

Clinical applications of circulating tumor cells in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a highly malignant tumor and ranked as the fourth cause of cancer-related mortality. The poor clinical prognosis is due to an advanced stage and resistance to systemic treatment. There are no obvious clinical symptoms in the early stage and the early diagnosis rate remains low. Novel effective biomarkers are important for early diagnosis and tumor surveillance to improve the survival of HCC patients. Circulating tumor cells (CTCs) are cancer cells shed from primary or metastatic tumor and extravasate into the blood system. The number of CTCs is closely related to the metastasis of various solid tumors. CTCs escape from blood vessels and settle in target organs, then form micro-metastasis. Epithelial-mesenchymal transformation (EMT) plays a crucial role in distant metastasis, which confers strong invasiveness to CTCs. The fact that CTCs can provide complete cellular biological information, which allows CTCs to be one of the most promising liquid biopsy targets. Recent studies have shown that CTCs are good candidates for early diagnosis, prognosis evaluation of metastasis or recurrence, and even a potential therapeutic target in patients with HCC. It is a new indicator for clinical application in the future. In this review, we introduce the enrichment methods and mechanisms of CTCs, and focus on clinical application in patients with HCC.

Circulating Tumor Cells in Hepatocellular Carcinoma: A Comprehensive Review and Critical Appraisal

Hepatocellular carcinoma (HCC) is the fifth most common neoplasm and a major cause of cancer-related death worldwide. There is no ideal biomarker allowing early diagnosis of HCC and tumor surveillance in patients receiving therapy. Liquid biopsy, and particularly circulating tumor cells (CTCs), have emerged as a useful tool for diagnosis and monitoring therapeutic responses in different tumors. In the present manuscript, we evaluate the current evidence supporting the quantitative and qualitative assessment of CTCs as potential biomarkers of HCC, as well as technical aspects related to isolation, identification, and classification of CTCs. Although the dynamic assessment of CTCs in patients with HCC may aid the decision-making process, there are still many uncertainties and technical caveats to be solved before this methodology has a true impact on clinical practice guidelines. More studies are needed to identify the optimal combination of surface markers, to increase the efficiency of ex-vivo expansion of CTCs, or even to target CTCs as a potential therapeutic strategy to prevent HCC recurrence after surgery or to hamper tumor progression and extrahepatic spreading.

Significance of circulating tumor cells in the portal vein regarding metastases and vascular invasion in hepatocellular carcinoma patients

BACKGROUND

Vascular invasion is an important risk factor of poor prognosis in hepatocellular carcinoma (HCC) patients. The detection of circulating tumor cells (CTCs) in the blood is direct evidence of tumor presence. There are few reports on CTCs and metastasis and vascular invasion of HCC. The purpose of this study was to analyze the significance of CTCs in the portal vein regarding metastases and vascular invasion in HCC patients.

METHODS

A total of 104 HCC patients diagnosed and treated in Zhengzhou University People's Hospital were enrolled. Surgery was performed in 60 individuals. Portal vein blood samples were collected before treatment for CTCs detection. We used the isolation by size of epithelial tumor cells (ISET) and fluorescence in situ hybridization (FISH) to enrich and classify CTCs from blood samples. The patients were divided into metastasis and nonmetastasis groups according to the metastasis status before treatment. Differences in clinical indicators such as alpha-fetoprotein (AFP) levels, tumor size, CTCs count, and macrovascular tumor thrombus between the two groups were analyzed as well as the associations of CTCs count with the above indicators. For individuals with postoperative pathology, the relationship between CTCs counts and microvascular invasion (MVI) was analyzed.

RESULTS

The amounts of portal vein CTCs were higher in patients with metastases compared with the nonmetastases group (20 vs. 7; z=3.795; P<0.001). Multivariate logistic regression analysis showed that the CTC count was a risk factor for HCC metastasis [odds ratio (OR) =1.044; 95% CI: 1.011-1.079]. The sensitivity and specificity of CTC count in predicting HCC metastasis were 82.93% and 52.38%, respectively. CTC count was significantly correlated with tumor size (rs=0.308; P=0.001), vascular invasion (z=4.211; P<0.001), and MVI (z=12.763; P=0.002). A threshold CTC count of seven showed the most significant power for predicting metastasis.

CONCLUSIONS

Vascular invasion positivity was closely related to HCC metastasis. Portal vein CTC count before treatment was correlated with vascular invasion and could be considered one of the factors affecting HCC metastasis. However, the ability of CTC count was limited in predicting HCC metastasis due to insufficient specificity.

Research progress on circulating tumor cells of hepatocellular carcinoma

Circulating tumor cells (CTCs) are the cells released from the primary tumor and found in the peripheral blood, which can colonize and develop at a distance through blood circulation. At present, the commonly used separation and detection methods of CTCs are mainly divided into physical methods, biological methods, and microfluidic chip-based methods. Monitoring CTC count and cell phenotype is of great significance for early screening and diagnosis of hepatocellular carcinoma (HCC). Moreover, the CTC count and cell phenotype are related to assessing the clinical efficacy of the treatment of HCC and the clinical stage of HCC patients. The CTCs count is also closely related to the overall survival, progression-free survival, and postoperative recurrence of patients with HCC.

Endoscopic Ultrasound-Guided Acquisition of Portal Venous Circulating Tumor Cells as a Potential Diagnostic and Prognostic Tool for Pancreatic Cancer

Background

Circulating tumor cells (CTCs) were a promising liquid biopsy for pancreatic cancer (PC) but circulate in low counts in peripheral blood. We evaluated the diagnostic and prognostic values of portal vein (PoV) CTCs in PC patients.

Methods

PoV was aspirated under EUS guidance from 40 patients with suspected pancreaticobiliary cancers. Epithelial–mesenchymal-transition-related subtypes of CTCs were identified via immunofluorescence using EpCAM and Twist antibodies. The diagnostic and prognostic performance of PoV CTCs was investigated by receiver-operating characteristic (AUC) curve and Kaplan–Meier survival analysis.

Results

In total, 40 patients including 31 with PC, 4 with non-pancreatic periampullary cancer and 5 with benign pancreatic diseases (BPD) were enrolled. CTCs were detected more in PoV compared with peripheral blood. PoV CTC numbers in BPD patients were lower than in PC patients. The number of PoV CTCs, especially mesenchymal-CTCs (M-CTCs), was positively correlated with the tumor burden, instead of epithelial-CTCs (E-CTCs). The combination of PoV CTC numbers and CA19-9 demonstrated better diagnostic efficiency (AUC value 0.987) than either alone in differentiating PC with BPD. Moreover, the diagnostic efficacy of PoV CTCs and M-CTCs were obviously better than that of E-CTCs and CA19-9 in distinguishing early and late stage PC. Lastly, high PoV CTC and M-CTC numbers were both associated with shorter overall survival.

Conclusion

Acquisition of the PoV samples in PC patients via EUS-guided procedures has been proved safe and feasible. PoV CTCs, especially M-CTCs, have great potentials in diagnosing and predicting the prognosis of PC, especially in combination with CA19-9.

Long-term survival and postoperative complications of pre-liver transplantation transarterial chemoembolisation in hepatocellular carcinoma: A systematic review and meta-analysis

OBJECTIVES

The aim of this meta-analysis was to conduct a contemporary systematic review of high quality non-randomised controlled trials to determine the effect of pre-liver transplantation (LT) transarterial chemoembolisation (TACE) on long-term survival and complications of hepatocellular carcinoma (HCC) patients.

BACKGROUND

TACE is used as a neoadjuvant therapy to mitigate waitlist drop-out for patients with HCC awaiting LT. Previous studies have conflicting conclusions on the effect of TACE on long-term survival and complications of HCC patients undergoing LT.

METHODS

CINAHL, Cochrane Controlled Register of Trials, Embase, PubMed, and Web of Science were systematically searched. Baseline characteristics included number of patients outside Milan criteria, tumour diameter, MELD score, and time on the waiting list. Primary outcomes included 3- and 5-year overall and disease-free survival. Secondary outcomes included tumour recurrence, 30-day postoperative mortality, and hepatic artery and biliary complications.

RESULTS

Twenty-one high-quality NRCTs representing 8242 patients were included. Tumour diameter was significantly larger in TACE patients (3.49 cm vs 3.15 cm, P = 0.02) and time on the waiting list was significantly longer in TACE patients (4.87 months vs 3.46 months, P = 0.05), while MELD score was significantly higher in non-TACE patients (10.81 vs 12.35, P = 0.005). All primary and secondary outcomes displayed non-significant differences.

CONCLUSION

Patients treated with TACE had similar survival and postoperative outcomes to non-TACE patients, however, they had worse prognostic features compared to non-TACE patients. These findings strongly support the current US and European clinical practice guidelines that neoadjuvant TACE can be used for patients with longer expected waiting list times (specifically >6 months). Randomised controlled trials would be needed to increase the quality of evidence.

Liquid Biopsy in Hepatocellular Carcinoma: Where Are We Now?

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer related death worldwide. Diagnostic, prognostic, and predictive biomarkers are urgently needed in order to improve patient survival. Indeed, the most widely used biomarkers, such as alpha-fetoprotein (AFP), have limited accuracy as both diagnostic and prognostic tests. Liver biopsy provides an insight on the biology of the tumor, but it is an invasive procedure, not routinely used, and not representative of the whole neoplasia due to the demonstrated intra-tumoral heterogeneity. In recent years, liquid biopsy, defined as the molecular analysis of cancer by-products, released by the tumor in the bloodstream, emerged as an appealing source of new biomarkers. Several studies focused on evaluating extracellular vesicles, circulating tumor cells, cell-free DNA and non-coding RNA as novel reliable biomarkers. In this review, we aimed to provide a comprehensive overview on the most relevant available evidence on novel circulating biomarkers for early diagnosis, prognostic stratification, and therapeutic monitoring. Liquid biopsy seems to be a very promising instrument and, in the near future, some of these new non-invasive tools will probably change the clinical management of HCC patients.

Detection of oncogenic mutations in paired circulating tumor DNA and circulating tumor cells in patients with hepatocellular carcinoma

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In paired analysis CTCs were detected in 27% and ctDNA in 77% of HCC patients.

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The TERT promoter mutation C228T was present in all patients with one or more ctDNA mutations, or detectable CTCs.

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CtDNA (or TERT C228T) positivity was associated with macrovascular invasion and poor survival of advanced HCC patients.

Background and aims

Circulating tumor cells (CTCs) or circulating tumor DNA (ctDNA) may be used for diagnostic or prognostic purposes in patients with hepatocellular carcinoma (HCC). We aim to determine whether CTCs or ctDNA are suitable to determine oncogenic mutations in HCC patients.

Methods

Twenty-six mostly advanced HCC patients were enrolled. 30 mL peripheral blood from each patient was obtained. CellSearch system was used for CTC detection. A sequencing panel covering 14 cancer-relevant genes was used to identify oncogenic mutations. TERT promoter C228T and C250T mutations were determined by droplet digital PCR.

Results

CTCs were detected in 27% (7/26) of subjects but at low numbers (median: 2 cells, range: 1–15 cells) and ctDNA in 77% (20/26) of patients. Mutations in ctDNA were identified in several genes: TERT promoter C228T (77%, 20/26), TP53 (23%, 6/26), CTNNB1 (12%, 3/26), PIK3CA (12%, 3/26) and NRAS (4%, 1/26). The TERT C228T mutation was present in all patients with one or more ctDNA mutations, or detectable CTCs. The TERT C228T and TP53 mutations detected in ctDNA were present at higher levels in matched primary HCC tumor tissue. The maximal variant allele frequency (VAF) of ctDNA was linearly correlated with largest tumor size and AFP level (Log10). CtDNA (or TERT C228T) positivity was associated with macrovascular invasion, and positivity of ctDNA (or TERT C228T) or CTCs (≥ 2) correlated with poor patient survival.

Conclusions

Oncogenic mutations could be detected in ctDNA from advanced HCC patients. CtDNA analysis may serve as a promising liquid biopsy to identify druggable mutations.

The clinical significance of CTC enrichment by GPC3-IML and its genetic analysis in hepatocellular carcinoma

Background

This research was to develop a special method for enriching Circulating tumor cells (CTCs) of Hepatocellular carcinoma (HCC) by Glypican-3 immunoliposomes (GPC3-IML), and to analyze the correlation between the CTCs count and tumor malignancy, as well as to investigate the mutation characteristics of CTC-derived NGS.

Results

In this study characterization of physical parameters was performed with the preparation of GPC3-IML. CTCs in peripheral blood of HCC patients were further separated and identified. Immunofluorescence was used to identify CTCs for further counting. By this means, the correlation between CTCs count and clinicopathological features was analyzed, and the genetic mutation characteristics of NGS derived from CTCs were investigated and compared with that of tissue NGS. Results showed that compared with EpCAM and vimentin, GPC-3 had a stronger CTCs separation ability. There was a correlation between "positive" count of CTCs (≥ 5 PV-CTC per 7.5 ml blood) and BCLC stage (P = 0.055). The result of CTC-NGS was consistent with that of tissue-NGS in 60% cases, revealing that KMT2C was a common highly-frequent mutated gene.

Conclusion

The combination of immunomagnetic separation of CTCs and anti-tumor marker identification technology can be regarded as a new technology of CTCs detection in peripheral blood of patients with HCC.

Trial registration EHBHKY2020-k-024. Registered 17 August 2020—Retrospectively registered

Early dynamic changes in circulating tumor cells and prognostic relevance following interventional radiological treatments in patients with hepatocellular carcinoma

The aim of this study was to investigate the dynamic changes of circulating tumor cells (CTCs) in patients with hepatocellular carcinoma (HCC) before and immediately after conducting a microwave ablation (MWA) and conventional transarterial chemoembolization (C-TACE). Additionally, the CTCs short-term dynamics were compared with the clinical course of the HCC-patients. Blood samples from 17 patients with HCC who underwent MWA (n = 10) or C-TACE (n = 7) were analyzed. Venous blood was taken before and immediately after the radiological interventions to isolate and quantify CTCs using flow cytometry. CTCs were identified as CD45- and positive for the markers ASGPR, CD146 and CD274 (PD-L1). Patients were followed of up to 2.2 years after the radiological intervention. CTCs were detected in 13 HCC patients (76%) prior to the radiological interventions. The rate of CTCs was significantly decreased after the intervention in patients treated with MWA (0.4 CTCs/mL of blood, p = 0.031). However, no significant differences were observed in patients who received C-TACE (0.3 CTCs/mL of blood, p = 0.300). Overall, no correlation was found between the CTCs rate before and after the radiological intervention and recurrence rate of HCC. This preliminary data could confirm the tumoricidal effects of MWA in patients with HCC by significantly decreasing CTCs rate. In our study, we were able to detect CTCs in HCC patients using 3 different tumor markers. This preliminary data shows significant lower CTCs detected in response to MWA. However, large-scale randomized clinical trials are needed to determine the future role and the prognostic relevance of CTCs following this treatment.

Evaluating the predictive power of circulating tumor cells for the prognosis of transarterial chemoembolization treatment on patients with advanced hepatocellular carcinoma

ABSTRACT

Explore the predictive power of Circulating Tumor Cells (CTCs) for evaluating the prognosis of transarterial chemoembolization (TACE) treatment on advanced hepatocellular carcinoma (HCC) patients, and use it to construct a prediction model.We retrospectively analyzed 43 patients with Barcelona Clinic Liver Cancer stage C HCC who underwent TACE treatment.The survival time of 43 advanced HCC patients were 2 to 60 months, with the median survival time of 12 months, 1-, 3-, and 5-year survival rates were 42.9%, 9.0%, and 3.6%, respectively. The OS of patients with high level of CTCs before TACE (CTC1 > 2) was significantly lower than that of patients with low level of CTCs (8 vs 12 months, P = .040), but there was no significant difference in PFS between the 2 groups (P = .926). Meanwhile, there was no significant difference in OS and PFS between patients with high level CTCs and those with low level CTCs at 1 week and 4 weeks after TACE (P all > .05). In univariate and multivariate Cox regression analysis, the number of lesions and CTC before TACE were the independent influencing factors for prognosis in these patients, and the HR was 3.01 and 1.20, respectively (all P < .05). The area under curve of COX regression model to predict OS increased with the increase of follow-up time, ranging from 0.56 to 0.85.The CTCs number before TACE is an effective biomarker for predicting the OS of advanced HCC patients. The joint prediction model based on CTCs and tumor number can effectively predict the prognosis of patients with advanced HCC.

Utility of Liquid Biopsy Analysis in Detection of Hepatocellular Carcinoma, Determination of Prognosis, and Disease Monitoring: A Systematic Review

BACKGROUND & AIMS

Liquid biopsies, or blood samples, can be analyzed to detect circulating tumor cells (CTCs), cell-free DNA (cfDNA), and extracellular vesicles, which might identify patients with hepatocellular carcinoma (HCC) or help determine their prognoses. We performed a systematic review of studies of analyses of liquid biopsies from patients with HCC and their comparisons with other biomarkers.

METHODS

We performed a systematic review of original studies published before December 1, 2019. We included studies that compared liquid biopsies alone and in combination with other biomarkers for the detection of HCC, performed multivariate analyses of the accuracy of liquid biopsy analysis in determining patient prognoses, or evaluated the utility of liquid biopsy analysis in monitoring treatment response.

RESULTS

Our final analysis included 112 studies: 67 on detection, 46 on determining prognosis, and 25 on treatment monitoring or selection. Ten studies evaluated assays that characterized cfDNA for detection of HCC in combination with measurement of α-fetoprotein (AFP)-these studies found that the combined measurement of cfDNA and AFP more accurately identified patients with HCC than measurement of AFP alone. Six studies evaluated assays for extracellular vesicles and 2 studies evaluated assays for CTC in detection of HCC, with and without other biomarkers-most of these studies found that detection of CTCs or extracellular vesicles with AFP more accurately identified patients with HCC than measurement of AFP alone. Detection of CTCs before surgery was associated with HCC recurrence after resection in 13 of 14 studies; cfDNA and extracellular vesicles have been studied less frequently as prognostic factors. Changes in CTC numbers before vs after treatment more accurately identify patients with HCC recurrence than pretreatment counts alone, and measurements of cfDNA can identify patients with disease recurrence or progression before changes can be detected by imaging. We found little evidence that analyses of liquid biopsies can aid in the selection of treatment for HCC. Quality assessment showed risk of bias in studies of HCC detection and determination of prognosis.

CONCLUSIONS

In a systematic review of 112 studies of the accuracy of liquid biopsy analysis, we found that assays for CTCs and cfDNA might aid in determining patient prognoses and monitoring HCC, and assays for cfDNA might aid in HCC detection, but there is a risk of bias in these studies. Studies must be standardized before we can assess the clinical utility of liquid biopsy analysis in the detection and management of patients with HCC.

Clinical value of circulating tumor cells for the diagnosis and prognosis of hepatocellular carcinoma (HCC): A systematic review and meta-analysis

BACKGROUND

To evaluate the clinical value of circulating tumor cell (CTC) detection in peripheral blood for the diagnosis and prognosis of hepatocellular carcinoma (HCC).

METHODS

Public databases were searched, and a meta-analysis was performed to determine the specificity, sensitivity, negative- likelihood ratio (NLR) and positive-likelihood ratio (PLR), and diagnostic odds ratio (dOR) of CTC detection for the diagnosis of HCC. Hazard ratios (HRs) and 95% confidence intervals (CIs) were analyzed for the association of CTC detection with overall survival (OS) and HCC recurrence. The Meta-DiSc 1.4 and Review Manager 5.2 software programs were used for statistical analysis.

RESULTS

Meta-analysis of 20 studies including 1191 patients showed that the specificity, sensitivity, NLR, PLR, and dOR of CTC testing for HCC diagnosis were 0.60 (95% CI = 0.57-0.63), 0.95 (95%CI = 0.93-0.96), 0.36 (95%CI = 0.28-0.48), 11.64 (95%CI = 5.85-23.14), and 38.94 (95%CI = 18.33-82.75), respectively. Meta-analysis of 18 studies including 1466 patients indicated that the OS of CTC-positive HCC patients was less than that of CTC-negative patients (HR = 2.31; 95% CI = 1.55-3.42; P < .01). Meta-analysis of 5 studies including 339 patients revealed that the presence of CTCs in peripheral blood significantly increased the risk of HCC recurrence (HR = 3.03, 95% CI = 1.89-4.86; P < .01).

CONCLUSION

CTCs in peripheral blood may be a useful marker for HCC diagnosis. In addition, the prognosis of CTC-positive HCC patients was significantly worse than that of CTC-negative HCC patients. Therefore, further studies are warranted to confirm the clinical potential of CTC detection in peripheral blood in patients with primary HCC.

Liver transplantation outcomes after transarterial chemotherapy for hepatocellular carcinoma

Background

Transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC) awaiting liver transplantation is widespread, although evidence that it improves outcomes is lacking and there exist concerns about morbidity. The impact of TACE on outcomes after transplantation was evaluated in this study.

Methods

Patients with HCC who had liver transplantation in the UK were identified, and stratified according to whether they received TACE between 2006 and 2016. Cox regression methods were used to estimate hazard ratios (HRs) for death and graft failure after transplantation adjusted for donor and recipient characteristics.

Results

In total, 385 of 968 patients (39·8 per cent) received TACE. Five-year patient survival after transplantation was similar in those who had or had not received TACE: 75·2 (95 per cent c.i. 68·8 to 80·5) and 75·0 (70·5 to 78·8) per cent respectively. After adjustment for donor and recipient characteristics, there were no differences in mortality (HR 0·96, 95 per cent c.i. 0·67 to 1·38; P = 0·821) or graft failure (HR 1·01, 0·73 to 1·40; P = 0·964). The number of TACE treatments (2 or more versus 1: HR 0·97, 0·61 to 1·55; P = 0·903) or the time of death after transplantation (within or after 90 days; P = 0·291) did not alter the outcome. The incidence of hepatic artery thrombosis was low in those who had or had not received TACE (1·3 and 2·4 per cent respectively; P = 0·235).

Conclusion

TACE delivered to patients with HCC before liver transplant did not affect complications, patient death or graft failure after transplantation.

Liquid biopsy, a paradigm shift in oncology: what interventional radiologists should know

The acquisition of adequate tumor sample is required to verify primary tumor type and specific biomarkers and to assess response to therapy. Historically, invasive surgical procedures were the standard methods to acquire tumor samples until advancements in imaging and minimally invasive equipment facilitated the paradigm shift image-guided biopsy. Image-guided biopsy has improved sampling yield and minimized risk to the patient; however, there are still limitations, such as its invasive nature and its consequent limitations to longitudinal tumor monitoring. The next paradigm shift in sampling technique will need to address these issues to provide a more reliable and less invasive technique. Recently, liquid biopsy (LB) has emerged as a non-invasive alternative to tissue sampling. This technique relies on direct sampling of blood or other bodily fluids in contact with the tumor in order to collect circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and circulating RNAs-in particular microRNA (miRNAs). Clinical applications of LB involve different steps of cancer patient management including screening, detection of disease recurrence, and evaluation of acquired resistance. With any paradigm shift, old techniques are often relegated to a secondary option. Although image-guided biopsies may appear as a passive spectator on the rapid advancement of LB, the two techniques may well be codependent. Interventional radiology may be integral to directly sample the liquid surrounding or draining from the tumor. In addition, LB may help to correctly select the patients for image-guided loco-regional treatments, to determine its treatment endpoint, and to early detect recurrence. KEY POINTS: • Liquid biopsy is a novel technology with potential high impact in the management of patients undergoing image-guided procedures. • Interventional radiology procedures may increase liquid biopsy sensitivity through direct fluid sampling. • Liquid biopsy techniques may provide a venue for improving patients' selection and enhance outcomes of interventional loco-regional therapies performed by interventional radiologists.

Circulating tumor cells are associated with poor outcomes in early-stage hepatocellular carcinoma: a prospective study

BACKGROUND

Previous studies evaluating association between circulating tumor cells (CTCs) and clinical outcomes in hepatocellular carcinoma (HCC) have shown inconsistent results due to suboptimal detection methods and patient heterogeneity.

METHODS

Patients undergoing surgery for early-stage HCC were prospectively enrolled. The CTC numbers were determined using a tapered slit platform, which detects CTCs based on the cell size and morphology. Survival and recurrence were evaluated, and Cox proportional hazards models were used to demonstrate the prognostic significance of CTC.

RESULTS

Of 105 patients, 25 had increased CTC numbers after surgery (ΔCTC > 0, defined as positive) and a significantly higher level of recurrence (p = 0.042). A positive ΔCTC was seen to be an independent predictor of recurrence (hazard ratio 2.28), along with hepatitis B virus infection, alanine aminotransferase level, and the presence of satellite nodules (all p < 0.05). Subgroup analyses showed that a positive ΔCTC was associated with lower survival and higher recurrence among patients with low alpha-fetoprotein levels and cirrhosis (all p < 0.05).

CONCLUSION

Calculation of ΔCTC based on the physical properties of the cells is predictive of recurrence in patients with early HCC undergoing surgery.

Tumor-proximal liquid biopsy to improve diagnostic and prognostic performances of circulating tumor cells

Circulating tumor cell (CTC) detection and numeration are becoming part of the common clinical practice, especially for breast, colon, and prostate cancer. However, their paucity in peripheral blood samples is an obstacle for their identification. Several groups have tried to improve CTC recovery rate by developing highly sensitive cellular and molecular detection methods. However, CTCs are still difficult to detect in peripheral blood. Therefore, their recovery rate could be increased by obtaining blood samples from vessels close to the drainage territories of the invaded organ, when the anatomical situation is favorable. This approach has been tested mostly during tumor resection surgery, when the vessels nearest to the tumor are easily accessible. Moreover, radiological (including echo‐guided based and endovascular techniques) and/or endoscopic routes could be utilized to obtain CTC samples close to the tumor in a less invasive way than conventional biopsies. The purpose of this article is to summarize the available knowledge on CTC recovery from blood samples collected close to the tumor (i.e., in vessels located in the drainage area of the primary tumor or metastases). The relevance of such an approach for diagnostic and prognostic evaluations will be discussed, particularly for pancreatic ductal adenocarcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, and non‐small‐cell lung cancer.

Liquid biopsy in hepatocellular carcinoma: circulating tumor cells and circulating tumor DNA

Hepatocellular carcinoma (HCC) is one of the most common cancers and a leading cause of death worldwide. Due to latent liver disease, late diagnosis, and nonresponse to systemic treatments, surgical resection and/or biopsy specimens are still generally considered as the gold standard by clinicians for clinical decision-making until now. Since the conventional tissue biopsy is invasive and contains small tissue samples, it is unable to represent tumor heterogeneity or monitor dynamic tumor progression. Therefore, it is imperative to find a new less invasive or noninvasive diagnostic strategy to detect HCC at an early stage and to monitor HCC recurrence. Over the past years, a new diagnostic concept known as “liquid biopsy” has emerged with substantial attention. Liquid biopsy is noninvasive and allows repeated analyses to monitor tumor recurrence, metastasis or treatment responses in real time. With the advanced development of new molecular techniques, HCC circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) detection have achieved interesting and encouraging results. In this review, we focus on the clinical applications of CTCs and ctDNA as key components of liquid biopsy in HCC patients.

The predictive values of serum dickkopf-1 and circulating tumor cells in evaluating the efficacy of transcatheter arterial chemoembolization treatment on hepatocellular carcinoma

In this study, we aim to explore the values of serum dickkopf-1 (DKK1) and circulating tumor cells (CTCs) in predicting the efficacy and prognosis of transcatheter arterial chemoembolization (TACE) treatment on patients with hepatocellular carcinoma (HCC). We did a retrospective analysis on 155 HCC patients who underwent TACE treatment. The patients were divided into response group (complete response and partial response) and nonresponse group (stable disease and progressive disease), and their changes in serum DKK1 and CTCs after TACE were recorded. Receiver operating characteristic curve and survival analysis were used to assess the predictive values of DKK1 and CTCs for TACE efficacy and long-term prognosis of HCC. We found that the levels of preoperative DKK1 and CTCs in patients with HCC had a moderate positive correlation (r = 0.54). After TACE treatment, the serum DKK1 and CTCs in the response group were significantly decreased compared to pretreatment levels (P < .05), whereas the nonresponse group showed significantly increased serum DKK1 and CTCs levels (P < .05). The largest area under the curve (AUC) was achieved when using >0.02 μg/L reduction in DKK1 level after 4 weeks of TACE to predict the efficacy of TACE treatment (AUC = 0.913, 95% confidence interval: 0.856-0.952, P < .001), with the sensitivity of 78.26% and the specificity of 88.07%. The overall survival, disease-free survival, and 5-year survival rates were all significantly lower in the patients with positive preoperative levels of serum DKK1 and CTCs. COX multivariate regression analysis showed that Eastern Cooperative Oncology Group score, and preoperative levels of serum DKK1 and CTCs are independent influencing factors for the prognosis of patients with HCC. Overall, our results demonstrated that serum DKK1 and CTCs levels were good biomarkers for predicting the efficacy and prognosis of TACE treatment in patients with HCC. Moreover, these parameters exhibited different characteristics, and might have different potential applications.

High Epithelial Cell Adhesion Molecule-Positive Circulating Tumor Cell Count Predicts Poor Survival of Patients with Unresectable Hepatocellular Carcinoma Treated with Transcatheter Arterial Chemoembolization

PURPOSE

To assess the role of epithelial cell adhesion molecule (EpCAM)-positive circulating tumor cell (CTC) count in predicting survival outcomes of transcatheter arterial chemoembolization in patients with unresectable hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

EpCAM-positive CTC counts were prospectively determined via CellSearch in peripheral blood of 97 patients with unresectable HCC treated with chemoembolization. The impact of each CTC cutoff point on overall survival (OS) was evaluated by univariate Cox regression analysis. Based on hazard ratio, patients were divided into 3 groups with low (CTC count 0/1), moderate (CTC count 2-5), and high (CTC count ≥ 6) levels. Correlation of CTC counts with survival was assessed by Cox proportional-hazards model.

RESULTS

Eighty-nine patients met inclusion criteria and were enrolled. On multivariate Cox regression analysis, CTC count was found to be an independent predictor of OS (P = .049) and progression-free survival (PFS; P = .007) in patients treated with chemoembolization. After adjustment for confounding factors, mortality risks in the high- and moderate-level groups were 2.819 times (95% confidence interval [CI], 1.218-6.526; P = .016) and 1.301 times (95% CI, 0.630-2.685; P = .477) greater, respectively, than in the low-level group. The risk of progression was 3.705 fold higher in the high-level group (95% CI, 1.628-8.433; P = .002) and 1.648 fold higher in the moderate-level group (95% CI, 0.843-3.223; P = .144) vs the low-level group.

CONCLUSIONS

High EpCAM-positive CTC count predicts poor survival of patients with unresectable HCC treated with chemoembolization.

Analysis of monosomy-3 in immunomagnetically isolated circulating melanoma cells in uveal melanoma patients

Monosomy-3 in primary uveal melanoma (UM) is associated with a high risk of metastasis and mortality. Although circulating melanoma cells (CMC) can be found in most UM patients, only approximately 50% of the patients develop metastases. We utilized a novel immuno-FISH assay to detect chromosome-3 in intact CMC isolated by dual immunomagnetic enrichment. Circulating melanoma cells were detected in 91% of the patients (n = 44) with primary non-metastatic UM, of which 58% were positive for monosomy-3. The monosomy-3 status of CMC corresponded to the monosomy-3 status of the primary tumor in 10 of the 11 patients where this could be tested. Monosomy-3 in the CMC was associated with an advanced tumor stage (P = 0.046) and was detected in all four patients who developed metastasis within the follow-up period of 4 yr. This non-invasive technique may enable the identification of UM patients at risk for metastasis particularly when a primary tumor specimen is unavailable.

Liquid biopsy in patients with hepatocellular carcinoma: Circulating tumor cells and cell-free nucleic acids

Hepatocellular carcinoma (HCC), with its high incidence and mortality rate, is one of the most common malignant tumors. Despite recent development of a diagnostic and treatment method, the prognosis of HCC remains poor. Therefore, to provide optimal treatment for each patient with HCC, more precise and effective biomarkers are urgently needed which could facilitate a more detailed individualized decision-making during HCC treatment, including the following; risk assessment, early cancer detection, prediction of treatment or prognostic outcome. In the blood of cancer patients, accumulating evidence about circulating tumor cells and cell-free nucleic acids has suggested their potent clinical utilities as novel biomarker. This concept, so-called “liquid biopsy” is widely known as an alternative approach to cancer tissue biopsy. This method might facilitate a more sensitive diagnosis and better decision-making by obtaining genetic and epigenetic aberrations that are closely associated with cancer initiation and progression. In this article, we review recent developments based on the available literature on both circulating tumor cells and cell-free nucleic acids in cancer patients, especially focusing on Hepatocellular carcinoma.

Utility of percutaneous radiofrequency ablation alone or combined with transarterial chemoembolization for early hepatocellular carcinoma

Percutaneous radiofrequency ablation (RFA) combined with transarterial chemoembolization (TACE) is an effective, standard therapy against small hepatocellular carcinoma (HCC). However, there is debate regarding the effectiveness of RFA combined with TACE (RFA/TACE) compared with RFA alone. These two approaches were compared for the treatment of early HCC. The present study examined 83 HCC tumors in 83 patients treated with RFA between April 2007 and August 2014 at three medical institutions. All HCCs were single hypervascular tumors, with a median diameter of 16 mm (range, 6-30 mm). The overall survival (OS) rate of all patients (n=83) was 97.5% at 1 year, 82.8% at 3 years and 48.6% at 5 years, and the local recurrence rate of all patients was 14.3% at 1 year, 32.3% at 3 years and 36.5% at 5 years. The tumor-free survival (TFS) rate of all patients was 95.1% at 1 year, 56.3% at 3 years and 23.4% at 5 years. Compared with RFA alone, RFA/TACE significantly improved OS (P<0.001), intrahepatic distant recurrence (IDR; P=0.038) and TFS (P=0.010). A univariate analysis of prognostic indicators revealed that age <70 years (P=0.008), aspartate transaminase <40 IU/l (P=0.003), alanine aminotransferase <40 IU/l (P=0.006) and platelet count >10×10⁴/µl (P=0.05) were associated with a high survival rate. Multivariate analysis identified RFA/TACE [hazard ratio (HR), 0.108; P=0.001] as an independent prognostic indicator. RFA/TACE was identified as the only independent indicator of IDR (HR: 0.467; P=0.042) and TFS (HR: 0.452; P=0.012). RFA/TACE improved OS rate, IDR and TFS compared with RFA alone. The data suggested that RFA/TACE should be considered for the treatment of single hypervascular HCC.

Novel specific markers for hepatocellular carcinoma: Perspective on clinical applications

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Despite continuous global efforts aimed at HCC eradication and improvements in various treatment techniques, the prognosis of HCC remains very poor. How to monitor malignant transformation of hepatocytes or diagnose HCC at early stage is still a medical challenge. A growing understanding of the multiple pathogenic factors including hepatitis B virus or hepatitis C virus infection, lipid accumulation, aflatoxin B1 intake and so on suggests that hepatocarcinogenesis is a multistep process. A large number of oncogenes or tumor suppressor genes have been identified. Early screening of HCC patients has been reported to confer a survival benefit. Although serum alpha-fetoprotein (AFP) and hepatoma-specific AFP have been used as conventional tumor markers, they often show false-positive results and lack sufficient sensitivity and specificity. In order to provide optimal treatment for each patient with HCC, more precise and effective biomarkers are urgently needed in all phases of management from early detection to staging, treatment monitoring, and prognosis evaluation. Recently, numerous studies have shown the clinical utility of novel blood-based biomarkers, such as circulating tumor cells, key signal molecules or specific proteins, long non-coding RNAs, and microRNAs. In this article, we will review some novel HCC-related biomarkers and discuss their future perspective on clinical applications.

Liquid Biopsy of Hepatocellular Carcinoma: Circulating Tumor-Derived Biomarkers

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide due to latent liver disease, late diagnosis, and nonresponse to systemic treatments. Till now, surgical and/or biopsy specimens are still generally used as a gold standard by the clinicians for clinical decision-making. However, apart from their invasive characteristics, tumor biopsy only mirrors a single spot of the tumor, failing to reflect current cancer dynamics and progression. Therefore, it is imperative to develop new diagnostic strategies with significant effectiveness and reliability to monitor high-risk populations and detect HCC at an early stage. In the past decade, the potent utilities of “liquid biopsy” have attracted intense concern and were developed to evaluate cancer progression in several clinical trials. “Liquid biopsies” represent a series of noninvasive tests that detect cancer byproducts easily accessible in peripheral blood, mainly including circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs) that are shed into the blood from the tumor sites. In this review, we focus on the recent developments in the field of “liquid biopsy” as well as the diagnostic and prognostic significance of CTCs and cfNAs in HCC patients.

Perioperative circulating tumor cell detection: Current perspectives

Primary cancer resections and in selected cases surgical metastasectomies significantly improve survival, however many patients develop recurrences. Circulating tumor cells (CTCs) function as an independent marker that could be used in the prognostication of different cancers. Sampling of blood and bone marrow compartments during cancer resections is a unique opportunity to increase individual tumor cell capture efficiency. This review will address the diagnostic and therapeutic potentials of perioperative tumor isolation and highlight the focus of future studies on characterization of single disseminated cancer cells to identify targets for molecular therapy and immune escape mechanisms.

The clinical role of 'liquid biopsy' in hepatocellular carcinoma

Circulating free tumor DNA (ctDNA) is DNA released from necrotic or apoptotic tumor cells into the bloodstream. Absolute levels of ctDNA, as well as genetic mutations and epigenetic changes detected in ctDNA are useful biomarkers of tumor biology, progression and response to therapy in many tumor types and recent evidence suggests they may be useful in hepatocellular carcinoma (HCC). ctDNA detected in blood, therefore, offers a minimally invasive, easily repeated 'liquid biopsy' of cancer, providing real-time dynamic analysis of tumor behavior and treatment response that could revolutionize both clinical and research practice in HCC. In this review, we provide a critical summary of the evidence for the utility of ctDNA as a diagnostic and prognostic biomarker in HCC.

Arterial Blood, Rather Than Venous Blood, is a Better Source for Circulating Melanoma Cells

Background

CTCs provide prognostic information and their application is under investigation in multiple tumor types. Of the multiple variables inherent in any such process, none is more important to outcome than the appropriateness of the sample source. To address this question, we investigated CTCs in paired peripheral venous and arterial blood specimens obtained from stage IV uveal melanoma patients.

Methods

Blood specimens were obtained from both common femoral arteries and antecubital veins in 17 uveal melanoma patients with multiple hepatic metastases for CTC measurements.

Finding

CTCs were detectable with greater frequency (100%) and in larger numbers (median 5, range 1 to 168) in all arterial blood specimens than in venous samples (52.9%; median 1, range 0 to 8). Patients with hepatic as well as extra-hepatic metastasis showed higher number of arterial CTCs, compared to patients with liver-only metastasis (p = 0.003). There was no significant association between the number of arterial CTCs and the tumor burden within the liver in patients who had liver-only metastases.

Interpretation

Our data indicate that arterial blood specimens might be a better source of circulating uveal melanoma cells. Although less conveniently processed, perhaps arterial blood should be evaluated as sample source for measurement of CTCs.

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CTCs were detectable in 100% of arterial blood obtained from metastatic uveal melanoma patients, while only 53% of venous blood was positive for CTCs.

CTCs have been investigated to provide prognostic information in multiple tumor types. Of the multiple variables, none is more important than the appropriateness of the sample source. Blood specimens were obtained from both femoral arteries and antecubital veins in 17 uveal melanoma patients with multiple hepatic metastases. CTCs were detectable with greater frequency (100%) and in larger numbers in all arterial blood specimens than in venous samples (52.9%). Our data indicate that arterial blood specimens might be a better source of circulating uveal melanoma cells. Although less convenient, arterial blood should be evaluated as sample source for measurement of CTCs.