Circulating Tumor Cells in Patients Undergoing Resection of Colorectal Cancer Liver Metastases. Clinical Utility for Long-Term Outcome: A Prospective Trial

A nomogram for predicting colorectal cancer liver metastasis using circulating tumor cells from the first drainage vein

PURPOSE

To use circulating tumor cells (CTC) from the first drainage vein (FDV) of the primary lesion and other clinically relevant parameters to construct a nomogram for predicting liver metastasis in colorectal cancer (CRC) patients, and to provide a theoretical basis for clinical diagnosis and treatment.

METHODS

Information from 343 CRC patients was collected and a database was established. Multivariate logistic analysis was used to identify independent factors for colorectal cancer liver metastasis(mCRC) and nomograms were constructed. Receiver operating characteristic curves(ROC), calibration plots, and decision curve analysis (DCA) were used to assess discrimination, agreement with actual risk, and the clinical utility of the prediction model, respectively.

RESULT

CTC levels in FDV were significantly higher in patients with liver metastasis than in those without liver metastasis. Logistic multivariate analysis showed that vascular invasion, T stage, carcinoembryonic antigen (CEA), CA19-9, and CTC could be used as predictors to construct nomograms. The nomograms showed good discriminatory ability in predicting mCRC, with area under the curve (AUC) values of 0.871 [95 % CI: 0.817-0.924) and 0.891 (95 % CI: 0.817-0.964) for the training and validation sets, respectively.] The calibration curves of both the training and validation sets showed that the model was effective in predicting the probability of mCRC. DCA was used to evaluate this predictive model and showed good net clinical benefit.

CONCLUSION

We developed and validated a nomogram model based on the combination of CTC in the FDV with other clinical parameters to better predict the occurrence of mCRC.

Circulating tumour cells predict recurrences and survival in head and neck squamous cell carcinoma patients

Patients with head and neck squamous cell carcinoma (HNSCC) are at a high risk of developing recurrence and secondary cancers. This study evaluates the prognostic and surveillance utilities of circulating tumour cells (CTCs) in HNSCC. A total of 154 HNSCC patients were recruited and followed up for 4.5 years. Blood samples were collected at baseline and follow-up. CTCs were isolated using a spiral microfluid device. Recurrence and death due to cancer were assessed during the follow-up period. In patients with HNSCC, the presence of CTCs at baseline was a predictor of recurrence (OR = 8.40, p < 0.0001) and death (OR= ∞, p < 0.0001). Patients with CTCs at baseline had poor survival outcomes (p < 0.0001). Additionally, our study found that patients with CTCs in a follow-up appointment were 2.5 times more likely to experience recurrence or death from HNSCC (p < 0.05) prior to their next clinical visit. Our study highlights the prognostic and monitoring utilities of CTCs' in HNSCC patients. Early identification of CTCs facilitates precise risk assessment, guiding treatment choices and ultimately enhancing patient outcomes.

Liquid biopsy in colorectal cancer

Liquid biopsy refers to a set of pathological samples retrieved from non-solid sources, such as blood, cerebrospinal fluid, urine, and saliva through non-invasive or minimally invasive approaches. In the recent decades, an increasing number of studies have focused on clinical applications and improving technological investigation of liquid biopsy biosources for diagnostic goals particularly in cancer. Materials extracted from these sources and used for medical evaluations include cells like circulating tumor cells (CTCs), tumor-educated platelets (TEPs), cell-free nucleic acids released by cells, such as circulating tumor DNA (ctDNA), cell-free DNA (cfDNA), cell-free RNA (cfRNA), and exosomes. Playing significant roles in the pathogenesis of human malignancies, analysis of these sources can provide easier access to genetic and transcriptomic information of the cancer tissue even better than the conventional tissue biopsy. Notably, they can represent the inter- and intra-tumoral heterogeneity and accordingly, liquid biopsies demonstrate strengths for improving diagnosis in early detection and screening, monitoring and follow-up after therapies, and personalization of therapeutical strategies in various types of human malignancies. In this review, we aim to discuss the roles, functions, and analysis approaches of liquid biopsy sources and their clinical implications in human malignancies with a focus on colorectal cancer.

Circulating tumour cells in gastrointestinal cancers: food for thought?

Gastrointestinal (GI) cancers account for 35% of cancer-related deaths, predominantly due to their ability to spread and generate drug-tolerant metastases. Arising from different locations in the GI system, the majority of metastatic GI malignancies colonise the liver and the lungs. In this context, circulating tumour cells (CTCs) are playing a critical role in the formation of new metastases, and their presence in the blood of patients has been correlated with a poor outcome. In addition to their prognostic utility, prospective targeting of CTCs may represent a novel, yet ambitious strategy in the fight against metastasis. A better understanding of CTC biology, mechanistic underpinnings and weaknesses may facilitate the development of previously underappreciated anti-metastasis approaches. Here, along with related clinical studies, we outline a selection of the literature describing biological features of CTCs with an impact on their metastasis forming ability in different GI cancers.

Circulating tumour cells are associated with histopathological growth patterns of colorectal cancer liver metastases

Histopathological Growth Patterns (HGPs) have prognostic and predictive value in patients with Colorectal Liver Metastases (CRLM). This study examined whether preoperative measurement of Circulating Tumour Cells (CTCs) is associated with HGP. CTCs were prospectively enumerated in 7.5 ml of blood using the FDA-approved CellSearch system in patients who underwent local treatment of CRLM with curative intent between 2008 and 2021. All CTC samples were collected on the day of local treatment. Patients treated with neoadjuvant chemotherapy for CRLM or with extrahepatic disease at the time of CTC sampling were excluded. HGP was scored retrospectively following the current consensus guidelines. The association between CTCs and HGP was investigated through multivariable logistic regression. Data were available for 177 patients, desmoplastic HGP (dHGP) was observed in 34 patients (19%). There were no statistically significant differences in patient and tumour characteristics between dHGP and non-dHGP at baseline. Patients with dHGP had longer overall - and disease-free survival (logrank p = 0.003 and 0.003, respectively) compared to patients with non-dHGP. CTCs were not detected in 25(74%) of dHGP patients and in 68(48%) of non-dHGP patients (chi-squared p = 0.006). Preoperative absence of CTCs was the only significant predictor for dHGP in multivariable logistic regression (Odds Ratio 2.7, 95%CI 1.1-6.8, p = 0.028), Table 3. Preoperative absence of CTCs is associated with dHGP in chemo naive CRLM patients without extrahepatic disease. Based on our results, CTC count alone is not sufficient to preoperatively identify HGPs, but integration of CTC count in multivariable prediction models may aid the preoperative identification of HGPs of CRLM.

MyCTC chip: microfluidic-based drug screen with patient-derived tumour cells from liquid biopsies

Cancer patients with advanced disease are characterized by intrinsic challenges in predicting drug response patterns, often leading to ineffective treatment. Current clinical practice for treatment decision-making is commonly based on primary or secondary tumour biopsies, yet when disease progression accelerates, tissue biopsies are not performed on a regular basis. It is in this context that liquid biopsies may offer a unique window to uncover key vulnerabilities, providing valuable information about previously underappreciated treatment opportunities. Here, we present MyCTC chip, a novel microfluidic device enabling the isolation, culture and drug susceptibility testing of cancer cells derived from liquid biopsies. Cancer cell capture is achieved through a label-free, antigen-agnostic enrichment method, and it is followed by cultivation in dedicated conditions, allowing on-chip expansion of captured cells. Upon growth, cancer cells are then transferred to drug screen chambers located within the same device, where multiple compounds can be tested simultaneously. We demonstrate MyCTC chip performance by means of spike-in experiments with patient-derived breast circulating tumour cells, enabling >95% capture rates, as well as prospective processing of blood from breast cancer patients and ascites fluid from patients with ovarian, tubal and endometrial cancer, where sensitivity to specific chemotherapeutic agents was identified. Together, we provide evidence that MyCTC chip may be used to identify personalized drug response patterns in patients with advanced metastatic disease and with limited treatment opportunities.

Predictive Efficacy of Circulating Tumor Cells in First Drainage Vein Blood from Patients with Colorectal Cancer liver Metastasis

Circulating tumor cells (CTCs) are associated with metastasis. However, the low rate of detection of CTCs in peripheral vein blood (PVB) limits their clinical application. In this study, we observed higher positive rates of CTC in first drainage vein blood (FDVB) relative to peripheral venous blood (P < 0.001). Moreover, the CTC content was related to liver metastasis, T stage and CA19-9 levels. Our collective data suggest that CTCs in FDVB have good predictive utility for risk of liver metastasis of colorectal cancer (CRC), in particular, metachronous liver metastasis.

Circulating tumour cell gene expression and chemosensitivity analyses: predictive accuracy for response to multidisciplinary treatment of patients with unresectable refractory recurrent rectal cancer or unresectable refractory colorectal cancer liver metastases

Background

Patients with unresectable recurrent rectal cancer (RRC) or colorectal cancer (CRC) with liver metastases, refractory to at least two lines of traditional systemic therapy, may receive third line intraarterial chemotherapy (IC) and targeted therapy (TT) using drugs selected by chemosensitivity and tumor gene expression analyses of liquid biopsy-derived circulating tumor cells (CTCs).

Methods

In this retrospective study, 36 patients with refractory unresectable RRC or refractory unresectable CRC liver metastases were submitted for IC and TT with agents selected by precision oncotherapy chemosensitivity assays performed on liquid biopsy-derived CTCs, transiently cultured in vitro, and by tumor gene expression in the same CTC population, as a ratio to tumor gene expression in peripheral mononuclear blood cells (PMBCs) from the same individual. The endpoint was to evaluate the predictive accuracy of a specific liquid biopsy precision oncotherapy CTC purification and in vitro culture methodology for a positive RECIST 1.1 response to the therapy selected.

Results

Our analyses resulted in evaluations of 94.12% (95% CI 0.71–0.99) for sensitivity, 5.26% (95% CI 0.01–0.26) for specificity, a predictive value of 47.06% (95% CI 0.29–0.65) for a positive response, a predictive value of 50% (95% CI 0.01–0.98) for a negative response, with an overall calculated predictive accuracy of 47.22% (95% CI 0.30–0.64).

Conclusions

This is the first reported estimation of predictive accuracy derived from combining chemosensitivity and tumor gene expression analyses on liquid biopsy-derived CTCs, transiently cultured in vitro which, despite limitations, represents a baseline and benchmark which we envisage will be improve upon by methodological and technological advances and future clinical trials.

The time-dependent changes in serum carcinoembryonic antigen impact on posthepatectomy outcomes of colorectal liver metastasis

BACKGROUND

Only a few studies have examined the impact of carcinoembryonic antigen variation in patients before and after curative resection of colorectal liver metastasis . This study examined the correlation between carcinoembryonic antigen levels and patient prognosis.

METHODS

Patients who underwent curative resection for colorectal liver metastasis between 2000 and 2017 were enrolled. This study examined patients with high preoperative carcinoembryonic antigen levels that normalized after resection of colorectal liver metastasis and the correlation between prognosis and time-dependent changes in carcinoembryonic antigen levels. The similarity in the risk of recurrence in patients with normal preoperative carcinoembryonic antigen levels was evaluated.

RESULTS

A total of 143 consecutive patients were included in the study cohort and classified into the normal preoperative (46 patients), normalized postoperative (57 patients), and elevated preoperative and postoperative (40 patients) carcinoembryonic antigen groups. All clinicopathologic characteristics were comparable between patients grouped according to carcinoembryonic antigen levels. The 5-year disease-free survival and overall survival rates for all patients were 30.4% and 56.0%, respectively. Multivariate analysis confirmed that elevated preoperative and postoperative carcinoembryonic antigen levels (hazard ratio = 1.73, 95% confidence interval: 1.04-2.87) were independently associated with poor disease-free survival; normalization of postoperative carcinoembryonic antigen (hazard ratio = 0.94, 95% confidence interval: 0.57-1.53) was statistically indistinguishable from normal preoperative carcinoembryonic antigen levels. The risk of recurrence was similar to that of patients with normal preoperative carcinoembryonic antigen levels CONCLUSION: Patients with elevated preoperative carcinoembryonic antigen levels that normalized after resection of colorectal liver metastasis were not at risk of poor disease-free survival. Elevated carcinoembryonic antigen levels after surgery are independent prognostic factors for disease-free survival.

Circulating Tumor Cell Kinetics and Morphology from the Liquid Biopsy Predict Disease Progression in Patients with Metastatic Colorectal Cancer Following Resection

The liquid biopsy has the potential to improve current clinical practice in oncology by providing real-time personalized information about a patient's disease status and response to treatment. In this study, we evaluated 161 peripheral blood (PB) samples that were collected around surgical resection from 47 metastatic colorectal cancer (mCRC) patients using the High-Definition Single Cell Assay (HDSCA) workflow. In conjunction with the standard circulating tumor cell (CTC) enumeration, cellular morphology and kinetics between time-points of collection were considered in the survival analysis. CTCs, CTC-Apoptotic, and CTC clusters were found to indicate poor survival with an increase in cell count from pre-resection to post-resection. This study demonstrates that CTC subcategorization based on morphological differences leads to nuanced results between the subtypes, emphasizing the heterogeneity within the CTC classification. Furthermore, we show that factoring in the time-point of each blood collection is critical, both for its static enumeration and for the change in cell populations between draws. By integrating morphology and time-based analysis alongside standard CTC enumeration, liquid biopsy platforms can provide greater insight into the pathophysiology of mCRC by highlighting the complexity of the disease across a patient's treatment.

Interrogating the interplay of angiogenesis and immunity in metastatic colorectal cancer

Colon cancer is the third most common malignancy and the fifth most frequent cause of death from neoplastic disease worldwide. At the time of diagnosis, more than 20% of patients already have metastatic disease. In the last 20 years, the natural course of the disease has changed due to major changes in the management of metastatic disease such as the advent of novel surgical and local therapy approaches as well as the introduction of novel chemotherapy drugs and targeted agents such as anti-epidermal growth factor receptor, anti-BRAF and antiangiogenics. Angiogenesis is a complex biological process of new vessel formation from existing ones and is an integral component of tumor progression supporting cancer cells to grow, proliferate and metastasize. Many molecules are involved in this proangiogenic process, such as vascular endothelial growth factor and its receptors on endothelial cells. A well-standardized methodology that is applied to assess angiogenesis in the tumor microenvironment is microvascular density by using immunohistochemistry with antibodies against endothelial CD31, CD34 and CD105 antigens. Even smaller molecules, such as the microRNAs, which are small non-coding RNAs, are being studied for their usefulness as surrogate biomarkers of angiogenesis and prognosis. In this review, we will discuss recent advances regarding the investigation of angiogenesis, the crosstalk between elements of the immune microenvironment and angiogenesis and how a disorganized tumor vessel network affects the trafficking of CD8+ T cells in the tumor bed. Furthermore, we will present recent data from clinical trials that combine antiangiogenic therapies with immune checkpoint inhibitors in colorectal cancer.

Survivin-positive circulating tumor cells as a marker for metastasis of hepatocellular carcinoma

BACKGROUND

Circulating tumor cells (CTCs) and survivin are indicators for tumor stage and metastasis, as well as epitheliomesenchymal transition, in various cancers, including hepatocellular cancer (HCC).

AIM

To explore the potential of survivin-positive CTCs, specifically, as a marker for tumor progression in HCC patients.

METHODS

We examined the survivin expression pattern in CTCs obtained from 179 HCC patients, and investigated the in vitro effects of survivin silencing and overexpression on the proliferation and invasion of HCC cells. CTC count and survivin expression in patient samples were examined using RNA in situ hybridization.

RESULTS

All 179 patients were positive for CTC markers, and 94.41% of the CTCs were positive for survivin. The CTC and survivin-positive CTC counts were significantly higher in the HCC patients than in the normal controls, and were significantly associated with tumor stage and degree of differentiation. Further, survivin overexpression was found to induce HepG2 cell proliferation, reduce apoptosis, and improve invasive ability.

CONCLUSION

Survivin shows upregulated expression (indicative of anti-apoptotic effects) in HCC. Thus, survivin-positive CTCs are promising as a predictor of HCC prognosis and metastasis, and their accurate measurement may be useful for the management of this cancer.

Circulating tumor cells in colorectal cancer in the era of precision medicine

Colorectal cancer (CRC) is one of the main causes of cancer-related morbidity and mortality across the globe. Although serum biomarkers such as carcinoembryonic antigen (CEA) and carbohydrate antigen 19–9 (CA-199) have been prevalently used as biomarkers in various cancers, they are neither very sensitive nor highly specific. Repeated tissue biopsies at different times of the disease can be uncomfortable for cancer patients. Additionally, the existence of tumor heterogeneity and the results of local biopsy provide limited information about the overall tumor biology. Against this backdrop, it is necessary to look for reliable and noninvasive biomarkers of CRC. Circulating tumor cells (CTCs), which depart from a primary tumor, enter the bloodstream, and imitate metastasis, have a great potential for precision medicine in patients with CRC. Various efficient CTC isolation platforms have been developed to capture and identify CTCs. The count of CTCs, as well as their biological characteristics and genomic heterogeneity, can be used for the early diagnosis, prognosis, and prediction of treatment response in CRC. This study reviewed the existing CTC isolation techniques and their applications in the clinical diagnosis and treatment of CRC. The study also presented their limitations and provided future research directions.

Detection and clinical significance of circulating tumor cells in colorectal cancer

Histopathological examination (biopsy) is the "gold standard" for the diagnosis of colorectal cancer (CRC). However, biopsy is an invasive method, and due to the temporal and spatial heterogeneity of the tumor, a single biopsy cannot reveal the comprehensive biological characteristics and dynamic changes of the tumor. Therefore, there is a need for new biomarkers to improve CRC diagnosis and to monitor and treat CRC patients. Numerous studies have shown that "liquid biopsy" is a promising minimally invasive method for early CRC detection. A liquid biopsy mainly samples circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), microRNA (miRNA) and extracellular vesicles (EVs). CTCs are malignant cells that are shed from the primary tumors and/or metastases into the peripheral circulation. CTCs carry information on both primary tumors and metastases that can reflect dynamic changes in tumors in a timely manner. As a promising biomarker, CTCs can be used for early disease detection, treatment response and disease progression evaluation, disease mechanism elucidation, and therapeutic target identification for drug development. This review will discuss currently available technologies for plasma CTC isolation and detection, their utility in the management of CRC patients and future research directions.

Evaluation of circulating tumor cells in colorectal cancer using flow cytometry

Objective

We aimed to evaluate the prognostic value of circulating tumor cells (CTCs) and the impact of intraoperative tumor manipulation on CTCs in colorectal cancer (CRC) patients.

Methods

We performed a prospective study on 40 patients with CRC stages I to IV who received curative surgery using the no-touch technique. Flow cytometry was used to identify CTCs in peripheral blood samples (4 mL/sample) collected at two surgical moments: skin incision (T1) and after surgical resection (T2). A threshold of ≥4 CTCs/4 mL blood was established for considering patients CTC positive.

Results

In the univariate analysis, CTC evaluation at T2 was correlated with female sex, vascular invasion, tumor localization in the colon and metastatic lymph nodes. In the multivariate analysis, only female sex and colon cancer maintained statistical significance. At a medium follow-up of 15 months (1–25 months), the mortality rate was 10% (n = 4), with no significant differences between the overall survival of T1 or T2 CTC-positive and CTC-negative patients.

Conclusions

Flow cytometry is a feasible CTC identification technique in CRC, and although surgical manipulation has no influence on CTC numbers, CTCs may serve as a prognostic and predictive factor.

Resectable Colorectal Cancer: Current Perceptions on the Correlation of Recurrence Risk, Microbiota and Detection of Genetic Mutations in Liquid Biopsies

Metastatic colorectal cancer (mCRC) remains a highly lethal malignancy, although considerable progress has resulted from molecular alterations in guiding optimal use of available treatments. CRC recurrence remains a great barrier in the disease management. Hence, the spotlight turns to newly mapped fields concerning recurrence risk factors in patients with resectable CRC with a focus on genetic mutations, microbiota remodeling and liquid biopsies. There is an urgent need for novel biomarkers to address disease recurrence since specific genetic signatures can identify a higher or lower recurrence risk (RR) and, thus, be used both as biomarkers and treatment targets. To a large extent, CRC is mediated by the immune and inflammatory interplay of microbiota, through intestinal dysbiosis. Clarification of these mechanisms will yield new opportunities, leading not only to the appropriate stratification policies, but also to more precise, personalized monitoring and treatment navigation. Under this perspective, early detection of post-operative CRC recurrence is of utmost importance. Ongoing trials, focusing on circulating tumor cells (CTCs) and, even more, circulating tumor DNA (ctDNA), seem to pave the way to a promising, minimally invasive but accurate and life-saving monitoring, not only supporting personalized treatment but favoring patients' quality of life, as well.

Small Cell Size Circulating Aneuploid Cells as a Biomarker of Prognosis in Resectable Non-Small Cell Lung Cancer

Objective

The size distribution of circulating aneuploid cells (CACs) and its clinical significance were investigated in resectable non-small cell lung cancer (NSCLC).

Patients and Methods

A total of 50 patients with resectable NSCLC were enrolled in this study. Blood samples (50 pre-surgery and 35 post-surgery) were collected and used for the detection of CAC chromosome 8 heteroploidy through the subtraction enrichment and immunostaining fluorescence in situ hybridization (SE-iFISH) method.

Results

Less than 20% small cell size and more than 80% large cell size CACs were detected. Karyotypes, including triploid, tetraploid, and multiploid, had varying distributions. The triploid subtype accounted for the majority of small cell size CACs, whereas the multiploid subtype accounted for the majority of large cell size CACs. We found that total small cell size and triploid small cell size CACs, but not large cell size CACs, derived from pre-surgery samples, were associated with shorter disease-free survival. Moreover, total small cell size and triploid small cell size CACs were associated with higher TNM stage and recurrence. Nevertheless, the variation between pre- and post-surgery CACs was not related to survival among patients with resectable NSCLC.

Conclusions

Pre-surgery small cell size CACs, especially the triploid subtype, could be regarded as a potential prognostic biomarker for patients with resectable NSCLC.

Surgery for Colorectal Cancer: A Trigger for Liver Metastases Development? New Insights into the Underlying Mechanisms

Surgery is a crucial intervention and provides the best chance of cure for patients with colorectal cancer. Experimental and clinical evidence, however, suggests that paradoxically surgery itself may precipitate or accelerate tumor recurrence and/or liver metastasis development. This review addresses the various aspects of surgery-induced metastasis formation and sheds light on the role of inflammation as potential trigger for metastasis development. Understanding these mechanisms may provide potential new perioperative interventions to improve treatment outcomes, and as such could transform the perioperative timeframe from a facilitator of metastatic progression to a window of opportunity to reduce the risk of liver metastasis development. Ultimately, this can potentially improve long-term survival rates and quality of life in patients with colorectal cancer.

Updates on liquid biopsy: current trends and future perspectives for clinical application in solid tumors

Despite advances in screening and therapeutics cancer continues to be one of the major causes of morbidity and mortality worldwide. The molecular profile of tumor is routinely assessed by surgical or bioptic samples, however, genotyping of tissue has inherent limitations: it represents a single snapshot in time and it is subjected to spatial selection bias owing to tumor heterogeneity. Liquid biopsy has emerged as a novel, non-invasive opportunity of detecting and monitoring cancer in several body fluids instead of tumor tissue. Circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), RNA (mRNA and microRNA), microvesicles, including exosomes and tumor "educated platelets" were recently identified as a source of genomic information in cancer patients which could reflect all subclones present in primary and metastatic lesions allowing sequential monitoring of disease evolution. In this review, we summarize the currently available information concerning liquid biopsy in breast cancer, colon cancer, lung cancer and melanoma. These promising issues still need to be standardized and harmonized across laboratories, before fully adopting liquid biopsy approaches into clinical practice.

Anterior Approach vs Conventional Hepatectomy for Resection of Colorectal Liver Metastasis: A Randomized Clinical Trial

Importance

Tumor relapse after partial hepatectomy for colorectal liver metastasis (CRLM) remains an unsolved issue. Intraoperative manipulation of the liver during conventional hepatectomy might enhance hematogenous tumor cell spread. The anterior approach is an alternative approach that may reduce intraoperative tumor cell dissemination.

Objective

To determine the efficacy and safety of the anterior approach compared with conventional hepatectomy in patients undergoing resection for CRLM.

Design, Setting, and Participants

This randomized clinical study evaluated the efficacy and safety of the anterior approach compared with conventional hepatectomy in adult patients with CRLM who were scheduled for hepatectomy from February 1, 2003, to March 31, 2012, at a tertiary-care hospital. A total of 80 patients with CRLM were randomized to the anterior approach and conventional hepatectomy groups in a 1:1 ratio. Bone marrow and blood samples were analyzed for disseminated tumor cells and circulating tumor cells (CTC) using cytokeratin 20 reverse transcriptase-polymerase chain reaction analysis. Data were analyzed from April 1 to December 1, 2018, using intention to treat.

Interventions

Anterior approach vs conventional hepatectomy.

Main Outcomes and Measures

The primary end point was intraoperative CTC detection in central blood samples after liver resection. Secondary end points included postoperative morbidity, mortality, and long-term survival.

Results

Among the 80 patients included in the analysis (48 men [60%]; mean [SD] age, 61 [10] years), baseline characteristics, including preoperative CTC detection, were comparable between both groups. There was no statistically significant difference in intraoperative CTC detection between patients in the conventional hepatectomy (5 of 21 [24%]) and anterior approach (6 of 22 [27%]) groups (P = .54). Except for a longer operating time in the anterior approach group (mean [SD], 171 [53] vs 221 [53] minutes; P < .001), there were no significant differences in intraoperative and postoperative outcomes between both study groups. Although detection of CTC was associated with poor overall (median, 46 [95% CI, 40-52] vs 81 [95% CI, 54-107] months; P = .03) and disease-free (median, 40 [95% CI, 34-46] vs 60 [95% CI, 46-74] months; P = .04) survival, there was no significant difference in overall (median, 73 [95% CI, 42-104] vs 55 [95% CI, 35-75] months; P = .43) and disease-free (median, 48 [95% CI, 40-56] vs 40 [95% CI, 28-52] months; P = .88) survival between the conventional hepatectomy and anterior approach groups. Also, there was no significant difference in patterns of recurrence between both groups.

Conclusions and Relevance

This randomized clinical trial found that the anterior approach was not superior to conventional hepatectomy in reducing intraoperative tumor cell dissemination in patients undergoing resection of CRLM.

Trial Registration

isrctn.org Identifier: ISRCTN45066244.

Liquid Biopsy in Colorectal Carcinoma: Clinical Applications and Challenges

Colorectal carcinoma (CRC) is characterized by wide intratumor heterogeneity with general genomic instability and there is a need for improved diagnostic, prognostic, and therapeutic tools. The liquid biopsy provides a noninvasive route of sample collection for analysis of circulating tumor cells (CTCs) and genomic material, including cell-free DNA (cfDNA), as a complementary biopsy to the solid tumor tissue. The solid biopsy is critical for molecular characterization and diagnosis at the time of collection. The liquid biopsy has the advantage of longitudinal molecular characterization of the disease, which is crucial for precision medicine and patient-oriented treatment. In this review, we provide an overview of CRC and the different methodologies for the detection of CTCs and cfDNA, followed by a discussion on the potential clinical utility of the liquid biopsy in CRC patient care, and lastly, current challenges in the field.

Perspectives of the Application of Liquid Biopsy in Colorectal Cancer

Colorectal cancer (CRC) is one of the most common gastrointestinal tumors and the second leading cause of cancer death worldwide. Since traditional biopsies are invasive and do not reflect tumor heterogeneity or monitor the dynamic progression of tumors, there is an urgent need for new noninvasive methods that can supplement and improve the current management strategies of CRC. Blood-based liquid biopsies are a promising noninvasive biomarker that can detect disease early, assist in staging, monitor treatment responses, and predict relapse and metastasis. Over time, an increasing number of experiments have indicated the clinical utility of liquid biopsies in CRC. In this review, we mainly focus on the development of circulating tumor cells and circulating tumor DNA as key components of liquid biopsies in CRC and introduce the potential of exosomal microRNAs as emerging liquid biopsy markers in clinical application for CRC.