Circulating tumor cells in perioperative esophageal cancer patients: quantitative assay system and potential clinical utility

Contemporaneous Perioperative Inflammatory and Angiogenic Cytokine Profiles of Surgical Breast, Colorectal, and Prostate Cancer Patients: Clinical Implications

Surgery-induced tumor growth acceleration and synchronous metastatic growth promotion have been observed for decades. Surgery-induced wound healing, orchestrated through growth factors, chemokines, and cytokines, can negatively impact patients harboring residual or metastatic disease. We provide detailed clinical evidence of this process in surgical breast, prostate, and colorectal cancer patients. Plasma samples were analyzed from 68 cancer patients who had not received treatment before surgery or adjuvant therapy until at least four weeks post-surgery. The levels of plasma cytokines, chemokines, and growth factors were simultaneously quantified and profiled using multiplexed immunoassays for eight time points sampled per patient. The immunologic processes are induced immediately after surgery in patients, characterized by a drastic short-term shift in the expression levels of pro-inflammatory and angiogenic molecules and cytokines. A rapid and significant spike in circulating plasma levels of hepatocyte growth factor (HGF), interleukin-6 (IL-6), placental growth factor (PLGF), and matrix metalloproteinase-9 (MMP-9) after surgery was noted. The rise in these molecules was concomitant with a significant drop in transforming growth factor-β1 (TGF-β1), platelet-derived growth factor (PDGF-AB/BB), insulin-like growth factor-1 (IGF-1), and monocyte chemoattractant protein-2 (MCP-2). If not earlier, each plasma analyte was normalized to baseline levels within 1-2 weeks after surgery, suggesting that surgical intervention alone was responsible for these effects. The effects of surgical tumor removal on disrupting the pro-inflammatory and angiogenic plasma profiles of cancer patients provide evidence for potentiating malignant progression. Our findings indicate a narrow therapeutic window of opportunity after surgery to prevent disease recurrence.

Multigene Profiling of Circulating Tumor Cells in Esophageal Squamous Cell Carcinoma Identifies Prognostic Cancer Driver Genes Associated with Epithelial-Mesenchymal-Transition Progression and Chemoresistance

We investigated the clinical significance of CTCs in cancer progression by detecting multiple cancer driver genes associated with epithelial-to-mesenchymal transition (EMT) at the transcript level. The 10-gene panel, comprising CCND1, ECT2, EpCAM, FSCN1, KRT5, KRT18, MET, TFRC, TWIST1, and VEGFC, was established for characterizing CTCs from mouse ESCC xenograft models and clinical ESCC peripheral blood (PB) samples. Correlations between gene expression in CTCs from PB samples (n = 77) and clinicopathological features in ESCC patients (n = 55) were examined. The presence of CTCs at baseline was significantly correlated with tumor size (p = 0.031). The CTC-high patients were significantly correlated with advanced cancer stages (p = 0.013) and distant metastasis (p = 0.029). High mRNA levels of TWIST1 (Hazard Ratio (HR) = 5.44, p = 0.007), VEGFC (HR = 6.67, p < 0.001), TFRC (HR = 2.63, p = 0.034), and EpCAM (HR = 2.53, p = 0.041) at baseline were significantly associated with a shorter overall survival (OS) in ESCC patients. This study also revealed that TWIST1 facilitates EMT and enhances malignant potential by promoting tumor migration, invasion, and cisplatin chemoresistance through the TWIST1-TGFBI-ZEB1 axis in ESCC, highlighting the prognostic and therapeutic potential of TWIST1 in clinical ESCC treatment.

Circulating Tumor Cell Enumeration for Serial Monitoring of Treatment Outcomes for Locally Advanced Esophageal Squamous Cell Carcinoma

We aim to reveal the clinical significance and potential usefulness of dynamic monitoring of CTCs to track therapeutic responses and improve survival for advanced ESCC patients. Peripheral blood (PB) (n = 389) and azygos vein blood (AVB) (n = 13) samplings were recruited prospectively from 88 ESCC patients undergoing curative surgery from 2017 to 2022. Longitudinal CTC enumeration was performed with epithelial (EpCAM/pan-cytokeratins/MUC1) and mesenchymal (vimentin) markers at 12 serial timepoints at any of the pre-treatment, all of the post-treatments/pre-surgery, post-surgery follow-ups for 3-year, and relapse. Longitudinal real-time CTC analysis in PB and AVB suggests more CTCs are released early at pre-surgery and 3-month post-surgery into the circulation from the CTRT group compared to the up-front surgery group. High CTC levels at pre-treatments, 1-/3-month post-surgery, unfavorable changes of CTC levels between all post-treatment/pre-surgery and 1-month or 3-month post-surgery (Hazard Ratio (HR) = 6.662, p < 0.001), were independent prognosticators for curative treatment. The unfavorable pre-surgery CTC status was independent prognostic and predictive for neoadjuvant treatment efficacy (HR = 3.652, p = 0.035). The aggressive CTC clusters were more frequently observed in AVB compared to PB. Its role as an independent prognosticator with relapse was first reported in ESCC (HR = 2.539, p = 0.068). CTC clusters and longitudinal CTC monitoring provide useful prognostic information and potential predictive biomarkers to help guide clinicians in improving disease management.

Circulating tumor cells detected in follow-up predict survival outcomes in tri-modality management of advanced non-metastatic esophageal cancer: a secondary analysis of the QUINTETT randomized trial

Background

Our aim was to establish if presence of circulating tumor cells (CTCs) predicted worse outcome in patients with non-metastatic esophageal cancer undergoing tri-modality therapy.

Methods

We prospectively collected CTC data from patients with operable non-metastatic esophageal cancer from April 2009 to November 2016 enrolled in our QUINTETT esophageal cancer randomized trial (NCT00907543). Patients were randomized to receive either neoadjuvant cisplatin and 5-fluorouracil (5-FU) plus radiotherapy followed by surgical resection (Neoadjuvant) or adjuvant cisplatin, 5-FU, and epirubicin chemotherapy with concurrent extended volume radiotherapy following surgical resection (Adjuvant). CTCs were identified with the CellSearch® system before the initiation of any treatment (surgery or chemoradiotherapy) as well as at 6-, 12-, and 24-months post-treatment. The threshold for CTC positivity was one and the findings were correlated with patient prognosis.

Results

CTC data were available for 74 of 96 patients and identified in 27 patients (36.5%) at a median follow-up of 13.1months (interquartile range:6.8-24.1 months). Detection of CTCs at any follow-up visit was significantly predictive of worse disease-free survival (DFS;hazard ratio [HR]: 2.44; 95% confidence interval [CI]: 1.41-4.24; p=0.002), regional control (HR: 6.18; 95% CI: 1.18-32.35; p=0.031), distant control (HR: 2.93; 95% CI: 1.52-5.65;p=0.001) and overall survival (OS;HR: 2.02; 95% CI: 1.16-3.51; p=0.013). After adjusting for receiving neoadjuvant vs. adjuvant chemoradiotherapy, the presence of CTCs at any follow-up visit remained significantly predictive of worse OS ([HR]:2.02;95% [Cl]:1.16-3.51; p=0.013) and DFS (HR: 2.49;95% Cl: 1.43-4.33; p=0.001). Similarly, any observed increase in CTCs was significantly predictive of worse OS (HR: 3.14; 95% CI: 1.56-6.34; p=0.001) and DFS (HR: 3.34; 95% CI: 1.67-6.69; p<0.001).

Conclusion

The presence of CTCs in patients during follow-up after tri-modality therapy was associated with significantly poorer DFS and OS regardless of timing of chemoradiotherapy.

Liquid Biopsy in Squamous Cell Carcinoma of the Esophagus and of the Head and Neck

Squamous cell carcinomas of the esophagus (ESCC) and of the head and neck (HNSCC) are two neoplasms that share common risk factors and have the same embryological origin, but a very different prognosis, the 5-year survival of HNSCC being almost double (40–50%) compared to the 5-year survival of ESCC (20%). Current guidelines emphasize the importance of screening for ESCC in patients diagnosed with head and neck cancers. A liquid biopsy is a novel tool for diagnosis, prognostic stratification, and personalized therapy. Liquid biopsy biomarkers for these two malignancies could help both their early detection, facilitate residual disease identification, and provide prognosis information. The present systematic review of the literature was aimed at describing the liquid biopsy biomarkers present in these two malignancies, with an emphasis on potential clinical applications.

Circulating Tumor Cells in Esophageal Squamous Cell Carcinoma - Mini Review

Esophageal cancer has high incidence and mortality rates and a low five-year survival rate of <15% owing to its strong capabilities of invasion, relapse and metastasis. The classic view holds that metastasis and diffusion is an advanced event during cancer progression, but recent studies show that distant diffusion of primary cancer cells may actually be an early event. Detection of circulating tumor cells (CTCs) in the circulation may indicate tumor spread, so CTCs are considered to be the key factor of metastatic cascade. In recent years, despite research progress on CTCs, there is a lack of systematic and important evidence to confirm the diagnostic, monitoring and prognostic values of CTCs in esophageal squamous cell carcinoma (ESCC). In this review, we clarify the relationship between CTC values and ESCC and provide more reliable evidence to improve the management and treatment of ESCC.

Δ133p53/FLp53 Predicts Poor Clinical Outcome in Esophageal Squamous Cell Carcinoma

Background

p53 isoform Δ133p53 is directly transactivated by p53 and antagonizes p53 activities in cancer progression. However, its correlation with prognosis and cancer recurrence in esophageal squamous cell carcinoma (ESCC) is still unclear.

Patients and Methods

Expression of Δ133p53 and Δ133p53/full-length p53 (FLp53) in tissues and serums of 180 ESCC patients was evaluated using qRT-PCR. Patients were divided into high- and low-expression groups according to the cutoff value determined by X-tile 3.6.1 software. Survival analysis was performed by the Kaplan-Meier method. Univariate and multivariate Cox survival analyses were applied to assess the hazard ratios (HRs).

Results

Tissue Δ133p53 expression and Δ133p53/FLp53 ratio were significantly increased in ESCC tissue compared with adjacent normal tissue. Pre-operative Δ133p53 expression and Δ133p53/FLp53 ratio in tissue or serum samples were positively associated with TNM stage and post-operative recurrence. Kaplan-Meier curve and multivariate cox regression analyses revealed that the tissue and serum Δ133p53/FLp53 ratios (cutoff value: 2.9160) were independent prognostic factors for overall survival (OS) and progression-free survival (PFS) in ESCC patients and showed no statistical difference in receiver-operating characteristic curve (ROC) analysis, while serum Δ133p53 showed no significant prognostic value. More importantly, the serum Δ133p53/FLp53 ratio in ESCC patients was significantly decreased within 72 h post tumor resection and patients with a consistently high serum Δ133p53/FLp53 ratio (≥2.9160) had higher recurrence rates than those with consistently low ratio values. In addition, dynamic detection in each follow-up timepoint showed that serum Δ133p53/FLp53 ratios were higher than 2.9160 upon recurrence, and they even increased prior to radiologic progression.

Conclusion

The serum Δ133p53/FLp53 ratio can be a novel predictor for survival outcome and may serve as a real-time parameter for monitoring recurrence in ESCC patients after surgery.

Tumor circulome in the liquid biopsies for digestive tract cancer diagnosis and prognosis

Digestive tract cancer is one of the main diseases that endanger human health. At present, the early diagnosis of digestive tract tumors mainly depends on serology, imaging, endoscopy, and so on. Although tissue specimens are the gold standard for cancer diagnosis, with the rapid development of precision medicine in cancer, the demand for dynamic monitoring of tumor molecular characteristics has increased. Liquid biopsy involves the collection of body fluids via non-invasive approaches, and analyzes biological markers such as circulating tumor cells, circulating tumor DNA, circulating cell-free DNA, microRNAs, and exosomes. In recent years, liquid biopsy has become more and more important in the diagnosis and prognosis of cancer in clinical practice due to its convenience, non-invasiveness, high specificity and it overcomes temporal-spatial heterogeneity. Therefore, this review summarizes the current evidence on liquid biopsies in digestive tract cancers in relation to diagnosis and prognosis.

Nanomedical detection and downstream analysis of circulating tumor cells in head and neck patients

The establishment of novel biomarkers in liquid biopsies of cancer patients has come more into focus in prognostic and diagnostic research efforts. Due to their prognostic relevance disseminated tumor cells or circulating tumor cells are the subject of intensive research and are discussed as early diagnostic indicators for treatment failure and the formation of micrometastases. A potential association of this early-systemic tumor component with poor prognosis of cancer patients could be already demonstrated for various entities including breast, colon, lung, melanoma, ovarian and prostate cancers. Thus, the detection of circulating tumor cells seems to be also applicable for minimal-invasive monitoring of therapy progress in head and neck cancer patients. A major problem of the use in clinical routine is that circulating tumor cells could not be detected by modern imaging techniques. To overcome these limitations highly sensitive detection methods and techniques for their molecular characterization are urgently needed allowing mechanistic understanding and targeting of circulating tumor cells. Especially the medical application of nanotechnology (nanomedical methods) has made valuable contributions to the field. Here, we want to provide a comprehensive overview on (nanomedical) detection methods for circulating tumor cells and discuss their merits, pitfalls and future perspectives especially for head and neck solid squamous cell carcinoma (HNSCC) patients.

Identification and validation of circulating exosomes-based liquid biopsy for esophageal cancer

Background

Early detection of esophageal squamous cell carcinoma (ESCC) recurrence is a key element for follow‐up care and surveillance. The aim of this study is to detect the level of circulating exosomes (CEs) in ESCC patient and clarify its clinical significance.

Methods

In this study, 200 serum samples of ESCC patients were obtained from the Zhejiang Cancer Hospital Biospecimen Repository. Total CEs were purified by selectively capturing epithelial cell adhesion molecule positive exosomes, using magnetic‐bead technique. enzyme‐linked immunosorbent assay (ELISA) was performed to measure the concentration level of CEs. The oncogenic potential of CEs was analyzed in vitro.

Results

Serum concentration of CEs was significantly higher in ESCC patients than in healthy controls (P < 0.01). Receiver‐operating characteristic curve analysis demonstrated that CEs concentration could distinguish patients with ESCC from healthy individuals with a sensitivity of 75% and a specificity of 85%. Kaplan‐Meier analysis demonstrated that the increased CEs concentration was associated with poor overall survival (P = 0.01) and progression free survival (P = 0.03) in ESCC patients. Multivariate cox regression analysis revealed that CEs concentration was an independent prognostic marker for overall survival in ESCC patients (P < 0.01). Results from transwell and wound scratching experiments showed that the CEs could promote cell migration and invasion.

Conclusions

This study clearly demonstrates that CEs from ESCC patients are stable enough to be measured and their levels in ESCC patients are significantly upregulated. Circulating exosomes could serve as a novel noninvasive biomarker for detection of ESCC. Their involvement in carcinogenesis must be further established.

Circulating tumor cells detected using fluid-assisted separation technique in esophageal squamous cell carcinoma

BACKGROUND AND AIM

Esophageal squamous cell carcinoma (ESCC) is one of the aggressive gastrointestinal tract cancers. Detection of circulating tumor cells (CTCs) in peripheral blood from patients with various malignancies has been reported to have diagnostic, prognostic, and therapeutic implications. We aimed to evaluate CTCs in patients with ESCC and assess the clinical significance of CTCs in the early diagnosis of ESCC.

METHODS

Peripheral blood samples for CTCs analyses were prospectively obtained from 73 patients with ESCC prior to treatment between March 2015 and June 2018. CTCs were detected using a centrifugal microfluidic system with a new fluid-assisted separation technique. Blood samples from 31 healthy volunteers were used as controls.

RESULTS

After creating a receiver operating characteristic curve to determine the optimal CTC threshold to differentiate patients with ESCC from healthy controls, sensitivity and specificity were most optimized at a CTC threshold of two per 7.5 mL of blood. Among 66 subjects with ≥ 2 CTCs per 7.5 mL of blood, 63 (95.5%) had ESCC. Among 38 subjects with < 2 CTCs per 7.5 mL of blood, 28 (73.7%) were healthy controls. When using this threshold, the sensitivity and specificity for differentiating patients with ESCC from healthy controls were 86.3% and 90.3%, respectively. CTC count was associated with tumor-node-metastasis stage, especially lymph node metastasis, but there was no correlation with any other relevant clinicopathologic variable.

CONCLUSIONS

Our results suggest that CTCs detected using fluid-assisted separation technique could be helpful for early diagnosis of ESCC. Further large-scale prospective studies are warranted to validate our findings.

Isolation of circulating tumor cells in patients undergoing surgery for esophageal cancer and a specific confirmation method

The clinical significance of circulating tumor cells (CTCs) in patients with esophageal squamous cell carcinoma (ESCC) who have undergone radical surgery was investigated. A novel confirmation method for identifying CTCs or circulating tumor microemboli (CTM) in ESCC was also investigated. Blood samples from 55 patients with ESCC were collected 1–3 days prior to surgery and 7 days post-surgery. All patients underwent curative thoracic esophagectomy and lymphadenectomy. Blood samples from 20 healthy volunteers were obtained as controls. Isolation by size of epithelial tumor cells (ISET) was performed also. The overall CTC detection rate was 52.7% preoperatively and 49.1% postoperatively. The presence of CTCs correlated with the Tumor-Node-Metastasis stage and the Log odds of positive lymph nodes. No significant difference in perioperative CTC transformation was discovered between the thoracoscopic and laparoscopic approach, and the open approach. The P40⁺/cluster of differentiation (CD)45⁻ phenotype was confirmed in the CTCs and CTM. ISET appeared to have high sensitivity for detecting CTCs within ESCC patients. Immunofluorescence staining for CD45 and P40 was a specific, accurate and convenient method for confirming the presence of CTCs or CTM in patients with ESCC, and is strongly recommended as a supplement to morphological analysis.

Surgical approach and the impact of epidural analgesia on survival after esophagectomy for cancer: A population-based retrospective cohort study

BACKGROUND

Esophagectomy for esophageal cancer carries high morbidity and mortality, particularly in older patients. Transthoracic esophagectomy allows formal lymphadenectomy, but leads to greater perioperative morbidity and pain than transhiatal esophagectomy. Epidural analgesia may attenuate the stress response and be less immunosuppressive than opioids, potentially affecting long-term outcomes. These potential benefits may be more pronounced for transthoracic esophagectomy due to its greater physiologic impact. We evaluated the impact of epidural analgesia on survival and recurrence after transthoracic versus transhiatal esophagectomy.

METHODS

A retrospective cohort study was performed using the linked Surveillance, Epidemiology and End Results (SEER)-Medicare database. Patients aged ≥66 years with locoregional esophageal cancer diagnosed 1994-2009 who underwent esophagectomy were identified, with follow-up through December 31, 2013. Epidural receipt and surgical approach were identified from Medicare claims. Survival analyses adjusting for hospital esophagectomy volume, surgical approach, and epidural use were performed. A subgroup analysis restricted to esophageal adenocarcinoma patients was performed.

RESULTS

Among 1,921 patients, 38% underwent transhiatal esophagectomy (n = 730) and 62% underwent transthoracic esophagectomy (n = 1,191). 61% (n = 1,169) received epidurals and 39% (n = 752) did not. Epidural analgesia was associated with transthoracic approach and higher volume hospitals. Patients with epidural analgesia had better 90-day survival. Five-year survival was higher with transhiatal esophagectomy (37.2%) than transthoracic esophagectomy (31.0%, p = 0.006). Among transthoracic esophagectomy patients, epidural analgesia was associated with improved 5-year survival (33.5% epidural versus 26.5% non-epidural, p = 0.012; hazard ratio 0.81, 95% confidence interval [0.70, 0.93]). Among the subgroup of esophageal adenocarcinoma patients undergoing transthoracic esophagectomy, epidural analgesia remained associated with improved 5-year survival (hazard ratio 0.81, 95% confidence interval [0.67, 0.96]); this survival benefit persisted in sensitivity analyses adjusting for propensity to receive an epidural.

CONCLUSION

Among patients undergoing transthoracic esophagectomy, including a subgroup restricted to esophageal adenocarcinoma, epidural analgesia was associated with improved survival even after adjusting for other factors.

Inflamed neutrophils sequestered at entrapped tumor cells via chemotactic confinement promote tumor cell extravasation

Systemic inflammation occurring around the course of tumor progression and treatment are often correlated with adverse oncological outcomes. As such, it is suspected that neutrophils, the first line of defense against infection, may play important roles in linking inflammation and metastatic seeding. To decipher the dynamic roles of inflamed neutrophils during hematogenous dissemination, we employ a multiplexed microfluidic model of the human microvasculature enabling physiologically relevant transport of circulating cells combined with real-time, high spatial resolution observation of heterotypic cell-cell interactions. LPS-stimulated neutrophils (PMNs) and tumor cells (TCs) form heterotypic aggregates under flow, and arrest due to both mechanical trapping and neutrophil-endothelial adhesions. Surprisingly, PMNs are not static following aggregation, but exhibit a confined migration pattern near TC-PMN clusters. We discover that PMNs are chemotactically confined by self-secreted IL-8 and tumor-derived CXCL-1, which are immobilized by the endothelial glycocalyx. This results in significant neutrophil sequestration with arrested tumor cells, leading to the spatial localization of neutrophil-derived IL-8, which also contributes to increasing the extravasation potential of adjacent tumor cells through modulation of the endothelial barrier. Strikingly similar migration patterns and extravasation behaviors were also observed in an in vivo zebrafish model upon PMN-tumor cell coinjection into the embryo vasculature. These insights into the temporal dynamics of intravascular tumor-PMN interactions elucidate the mechanisms through which inflamed neutrophils can exert proextravasation effects at the distant metastatic site.

Significant prognostic value of circulating tumor cells in esophageal cancer patients: A meta-analysis

Esophageal cancer is the sixth leading cause of cancer death worldwide. Detection of circulating tumor cells (CTCs) is emerging as a novel strategy for predicting cancer patient prognosis. Here we performed a comprehensive literature search to identify relevant articles in EMbase, PubMed, EBSCO, OVID, Cochrane Database, CNKI, WanFangdata and VIPdata. Meta-analysis was conducted using Stata12.0 software, according to the inclusion and exclusion criteria, extracted data and assessment methodology. Thirteen eligible literature studies were included with a total of 979 esophageal squamous cell carcinoma patients, including 424 CTC-positive and 684 CTC-negative cases. Meta-analysis showed that the presence of CTCs was associated with both worse progression-free/disease-free survival [hazard ration (HR) = 2.32, 95% confidence interval (CI) = 1.57 - 3.43, p < 0.001] and poorer overall survival [HR = 2.64, 95% CI = 1.69 - 4.14, p < 0.001]. Further subgroup analyses demonstrated that CTC-positive patients also showed worse progression-free/disease-free survival and poorer overall survival in different subsets. In summary, our meta-analysis provides strong evidence that detection of CTCs in the peripheral blood is an independent prognostic indicator of poor outcome for esophageal squamous cell carcinoma patients.

Circulating tumor cell detection: A direct comparison between negative and unbiased enrichment in lung cancer

Circulating tumor cells (CTCs), isolated as a 'liquid biopsy', may provide important diagnostic and prognostic information. Therefore, rapid, reliable and unbiased detection of CTCs are required for routine clinical analyses. It was demonstrated that negative enrichment, an epithelial marker-independent technique for isolating CTCs, exhibits a better efficiency in the detection of CTCs compared with positive enrichment techniques that only use specific anti-epithelial cell adhesion molecules. However, negative enrichment techniques incur significant cell loss during the isolation procedure, and as it is a method that uses only one type of antibody, it is inherently biased. The detection procedure and identification of cell types also relies on skilled and experienced technicians. In the present study, the detection sensitivity of using negative enrichment and a previously described unbiased detection method was compared. The results revealed that unbiased detection methods may efficiently detect >90% of cancer cells in blood samples containing CTCs. By contrast, only 40-60% of CTCs were detected by negative enrichment. Additionally, CTCs were identified in >65% of patients with stage I/II lung cancer. This simple yet efficient approach may achieve a high level of sensitivity. It demonstrates a potential for the large-scale clinical implementation of CTC-based diagnostic and prognostic strategies.

Circulating tumor cells and circulating tumor DNA: What surgical oncologists need to know?

As a result of recent progress in detection techniques, circulating tumor DNA (ctDNA) and circulating tumor cells (CTC) can now be accurately detected in the blood of most cancer patients. While these new biomarkers can provide a better understanding of key biological mechanisms underlying cancer growth and dissemination, they also open up a wide range of possible clinical applications in medical oncology, radiation oncology and surgical oncology. In this review, we summarize the results obtained with ctDNA and CTC together with their potential future clinical applications in the field of surgical oncology, with particular focus on the perioperative setting of various types of cancer. These applications include, but are not limited to, cancer screening, early diagnosis, prognostic assessment, evaluation and management of preoperative systemic or local therapies, post-surgical detection of minimal residual disease and early detection of cancer relapse.

Circulating Tumour Cells as an Independent Prognostic Factor in Patients with Advanced Oesophageal Squamous Cell Carcinoma Undergoing Chemoradiotherapy

The role of circulating tumour cells (CTCs) in advanced oesophageal cancer (EC) patients undergoing concurrent chemoradiotherapy (CCRT) remains uncertain. A negative selection protocol plus flow cytometry was validated to efficiently identify CTCs. The CTC number was calculated and analysed for survival impact. The protocol’s efficacy in CTC identification was validated with a recovery rate of 44.6 ± 9.1% and a coefficient of variation of 20.4%. Fifty-seven patients and 20 healthy donors were enrolled. Initial staging, first response to CRT, and surgery after CRT were prognostic for overall survival, with P values of <0.0001, <0.0001, and <0.0001, respectively. The CTC number of EC patients is significantly higher (P = 0.04) than that of healthy donors. Multivariate analysis for disease-specific progression-free survival showed that surgery after response to CCRT, initial stage, and CTC number (≥21.0 cells/mL) played independent prognostic roles. For overall survival, surgery after CCRT, performance status, initial stage, and CTC number were significant independent prognostic factors. In conclusion, a negative selection plus flow cytometry protocol efficiently detected CTCs. The CTC number before CCRT was an independent prognostic factor in patients with unresectable oesophageal squamous cell carcinoma. Further large-scale prospective studies for validation are warranted.

Aptamer-Mediated Transparent-Biocompatible Nanostructured Surfaces for Hepotocellular Circulating Tumor Cells Enrichment

Circulating tumor cells (CTCs) have been considered as the origin of cancer metastasis. Thus, detection of CTCs in peripheral blood is of great value in different types of solid tumors. However, owing to extremely low abundance of CTCs, detection of them has been technically challenging. To establish a simple and efficient method for CTCs detection in patients with hepatocellular carcinoma (HCC), we applied biocompatible and transparent HA/CTS (Hydroxyapatite/chitosan) nanofilm to achieve enhanced topographic interactions with nanoscale cellular surface components, and we used sLex-AP (aptamer for carbohydrate sialyl Lewis X) to coat onto HA/CTS nanofilm for efficient capture of HCC CTCs, these two functional components combined to form our CTC-^BioTChip platform. Using this platform, we realized HCC CTCs' capture and identification, the average recovery rate was 61.6% or more at each spiking level. Importantly, our platform identified CTCs (2±2 per 2 mL) in 25 of 42 (59.5%) HCC patients. Moreover, both the positivity rate and the number of detected CTCs were significantly correlated with tumor size, portal vein tumor thrombus, and the TNM (tumor-node-metastasis) stage. In summary, our CTC-^BioTChip platform provides a new method allowing for simple but efficient detection of CTCs in HCC patients, and it holds potential of clinically usefulness in monitoring HCC prognosis and guiding individualized treatment in the future.

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.

Prognostic significance of circulating tumor cells in esophageal carcinoma: a meta-analysis

PURPOSE

The prognostic significance of circulating tumor cells (CTCs) in esophageal carcinoma (EC) is controversial. We aim to assess its association with clinicopathological and prognostic relevance in EC by using a meta-analysis.

METHODS

We searched PubMed, Cochrane Database, Embase databases, and the references in relevant studies that assessed the clinicopathological or prognostic relevance of CTCs in peripheral blood of patients with EC. Statistical analyses were conducted by using Stata software to calculate the pooled odds ratio (OR), hazard ratio (HR), and 95% confidence intervals (CIs) using fixed or random-effects models according to the heterogeneity of included studies. The subgroup analyses were performed according to ethnicity, histological type, and detection method.

RESULTS

Sixteen trials containing 1,260 patients were included for analysis. Pooled results showed that presence of CTCs was significantly associated with poor overall survival (HR =1.71, 95% CI [1.30, 2.12], P<0.001) and progression-free survival (HR =1.67, 95% CI [1.19, 2.15], P<0.001) in EC patients. Subgroup analysis indicated that presence of CTCs was closely associated with worse overall survival (Asian: HR =1.66, 95% CI [1.24, 2.08], P<0.001; squamous cell carcinoma [SCC]: HR =1.66, 95% CI [1.24, 2.08], P<0.001; no polymerase chain reaction [PCR]: HR =2.08, 95% CI [1.40, 2.76], P<0.001) and progression-free survival (Asian: HR =1.63, 95% CI [1.15, 2.12], P<0.001; SCC: HR =1.63, 95% CI [1.15, 2.12], P<0.001; PCR: HR =1.63, 95% CI [1.15, 2.12], P<0.001). Additionally, ORs showed that presence of CTCs was significantly correlated with tumor node metastasis (TNM) staging (overall: OR = 1.96, 95% CI [1.34, 2.87], P=0.001; Asian: OR =2.09, 95% CI [1.37, 3.19], P=0.001; SCC: OR =1.97, 95% CI [1.21, 3.07], P=0.003; PCR: OR =2.23, 95% CI [1.43, 3.47], P<0.001), venous invasion (overall: OR =2.23, 95% CI [1.46, 3.40], P<0.001; Asian: OR =2.23, 95% CI [1.46, 3.40], P<0.001; SCC: OR =2.23, 95% CI [1.46, 3.40], P<0.001; PCR: OR =2.23, 95% CI [1.46, 3.40], P<0.001), lymph node metastasis (overall: OR =2.41, 95% CI [1.50, 3.86], P<0.001; Asian: OR =2.89, 95% CI [1.80, 4.65], P<0.001; SCC: OR =2.44, 95% CI [1.47, 4.07], P=0.001; PCR: OR =2.89, 95% CI [1.80, 4.65], P<0.001) and distant metastasis (Asian: OR =2.68, 95% CI [1.01, 7.08], P=0.047) in patients with EC.

CONCLUSION

The presence of CTCs indicates a poor prognosis in EC patients, especially in Asian and SCC patients. Further well-designed prospective studies are recommended to explore the clinical applications of CTCs in patients with EC.

Circulating tumor cell isolation during resection of colorectal cancer lung and liver metastases: a prospective trial with different detection techniques

BACKGROUND

Colorectal cancer (CRC) metastasectomy improves survival, however most patient develop recurrences. Circulating tumor cells (CTCs) are an independent prognostic marker in stage IV CRC. We hypothesized that CTCs can be enriched during metastasectomy applying different isolation techniques.

METHODS

25 CRC patients undergoing liver (16 (64%)) or lung (9 (36%)) metastasectomy were prospectively enrolled (clinicaltrial.gov identifier: NCT01722903). Central venous (liver) or radial artery (lung) tumor outflow blood (7.5 ml) was collected at incision, during resection, 30 min after resection, and on postoperative day (POD) 1. CTCs were quantified with 1. EpCAM-based CellSearch® system and 2. size-based isolation with a novel filter device (FMSA). CTCs were immunohistochemically identified using CellSearch®'s criteria (cytokeratin 8/18/19+, CD45- cells containing a nucleus (DAPI+)). CTCs were also enriched with a centrifugation technique (OncoQuick®).

RESULTS

CTC numbers peaked during the resection with the FMSA in contrast to CellSearch® (mean CTC number during resection: FMSA: 22.56 (SEM 7.48) (p = 0.0281), CellSearch®: 0.87 (SEM ± 0.44) (p = 0.3018)). Comparing the 2 techniques, CTC quantity was significantly higher with the FMSA device (range 0-101) than CellSearch® (range 0-9) at each of the 4 time points examined (P < 0.05). Immunofluorescence staining of cultured CTCs revealed that CTCs have a combined epithelial (CK8/18/19) and macrophage (CD45/CD14) phenotype.

CONCLUSIONS

Blood sampling during CRC metastasis resection is an opportunity to increase CTC capture efficiency. CTC isolation with the FMSA yields more CTCs than the CellSearch® system. Future studies should focus on characterization of single CTCs to identify targets for molecular therapy and immune escape mechanisms of cancer cells.

Circulating Tumor Cells in Gastrointestinal Cancer: Current Practices and Future Directions

GI cancers are the leading cause of cancer-related death worldwide primarily due to a combination of late presentation and aggressive biology. The lack of adequate biomarkers for screening, diagnosis, staging, and prognosis confounds clinical decision-making and delays potentially effective therapies. Circulating tumor cells (CTCs) are a new biomarker with particular promise in GI cancers, potentially offering clinicians and researchers real-time access to tumor tissue in a reliable, safe, and cost-effective manner. Preliminary studies have investigated the potential clinical utility of CTCs for all GI cancer types with promising results. Furthermore, advances in single cell analytics have been successfully applied to CTCs, allowing for exciting new clinical and research applications. In this chapter, we will review the current state of CTC research in GI cancers as well as the potential future applications that are currently being developed.

[Blood-based Tumor Markers in Lung Cancer]

In recent years, "liquid biopsy" received enormous attention as a new detecting method. As a non-invasive tumor screening method, the applications of liquid biopsy include early detection, monitoring relapse, assessment of therapy and molecule expression in lung cancer. The main source of liquid biopsy comes from circulating tumor cells (CTCs), ctDNA, and so on. This review will explore the biological characteristics, detection technologies and clinical applications of CTCs, ctDNA and other tumor markers in lung cancer and summarize liquid biopsy which in accord with three important criteria of high sensitivity (high specificity), clinical utility and repeatability, especially a new method of ligand-targeted PCR (LT-PCR) that showed a high sensitivity of 67.2% in stage I lung cancer. We expect that "liquid biopsy" could be really explored from scientific research to clinical application.

Prognostic Role of Circulating Tumor Cells during Induction Chemotherapy Followed by Curative Surgery Combined with Postoperative Radiotherapy in Patients with Locally Advanced Oral and Oropharyngeal Squamous Cell Cancer

Background

The prognostic role of circulating tumor cells (CTCs) after induction chemotherapy using docetaxel, cisplatin and fluorouracil (TPF) prior to surgery and adjuvant (chemo)radiation in locally advanced oral squamous cell cancer (OSCC) was evaluated.

Methods

In this prospective study, peripheral blood samples from 40 patients of the phase II study TISOC-1 (NCT01108042) with OSCC before, during, and after treatment were taken. CTCs were quantified using laser scanning cytometry of anti– epithelial cell adhesion molecule–stained epithelial cells. Their detection was correlated with clinical risk factors, recurrence-free (RFS) and overall survival (OS).

Results

Before starting the treatment CTCs were detected in 32 of 40 patients (80%). The median number at baseline was 3295 CTCs/ml. The median maximal number of CTCs during treatment was 5005 CTCs/ml. There was a significant increase of CTCs before postoperative radiotherapy compared to baseline before 1^st cycle of IC (p = 0.011), 2^nd cycle of IC (p = 0.001), 3^rd cycle of IC (p = 0.004), and before surgery (p = 0.002), but not compared to end of therapy (p = 0.118). CTCs at baseline >median was also associated to risk of recurrence (p = 0.014). Maximal CTCs during therapy >median was more frequently observed in tumors of the oral cavity (p=0.022) and related to higher risk of death during follow-up (p = 0.028). Patients with CTCs at baseline >median value had significant lower RFS than patients with CTCs at baseline <median value (p = 0.025). Patients with maximal CTCs values >median during the complete course of therapy had a significantly lower OS than patients with values <median (p = 0.049). Finally, the multivariate analysis revealed that OS was significantly lower in patients with maximal CTCs during treatment higher than the median value (HR=6.151; CI: 1.244-30.420).

Conclusions

Baseline CTCs and maximal CTCs during therapy both seem to be good prognostic markers for OSCC when treated by TPF induction chemotherapy, surgery, and postoperative (chemo)radiation.

The Clinical Utility of Circulating Tumor Cells in Breast Cancer Patients: Detection by a Quantitative Assay of h-MAM Gene Expression

The aim of this study was to evaluate tumor markers of molecular abnormalities that display tissue specificity, as to detect circulating tumor cells (CTCs) in breast cancer patients. Quantitative real-time RT-PCR was used to determine h-MAM, BCSG1, CK19, and c-erbB2 mRNA levels in peripheral blood (PB) of breast cancer patients. Results were compared with other epithelial cancers (lung or esophagus cancer), benign breast disease, and healthy individuals. We found that h-MAM mRNA was only detectable in the PB of patients with breast cancer (49 of 65, 75.4%), but not in patients with other epithelial cancers, benign breast disease, or healthy individuals. No significant differences in the expression level and positive detection rate of BCSG1, CK19, and c-erbB2 mRNA were observed between breast cancer and other epithelial cancers. Furthermore, the expression level and positive detection rate of h-MAM mRNA in PB were significantly correlated to the breast cancer pathologic stage (p=0.012 and p=0.015, respectively). Chemotherapy, radiotherapy, or total tumor resection (after 7 days of treatment) resulted in a significant decrease in the expression level of h-MAM mRNA in PB compared to the levels prior to the treatment (p<0.001). Importantly, an increase in h-MAM mRNA expression was detected in patients immediately after surgery, as well as 3 days post-surgery. These results indicate that the quantitative analysis of h-MAM mRNA is a useful tool for detecting CTCs in breast cancer patients, and can have a potential diagnostic utility in early micrometastasis, clinical evaluation of cancer treatment efficacy, and post-treatment monitoring of breast cancer patients.

Enrichment and enumeration of circulating tumor cells by efficient depletion of leukocyte fractions

BACKGROUND

Enumeration and characterization of circulating tumor cells (CTCs) can provide information on patient prognosis and treatment efficacy. However, CTCs are rare, making their isolation a major technological challenge. We developed a technique for enrichment, and subsequent characterization of CTCs based on efficient depletion of human leukocytes.

METHODS

The technique (CanPatrolTM CTC enrichment) we developed is based on red blood cell lysis to remove erythrocytes, followed by depletion of CD45+ leukocytes using a magnetic bead separation method, and subsequent isolation of CTCs by virtue of their larger size, compared with leukocytes. We also demonstrated that fluorescence in situ hybridization (FISH) and genetic abnormalities analysis could be performed on the isolated CTCs.

RESULTS

The spiking experiments showed that the average efficacy of leukocytes depletion was 99.98% and the average tumor cells recovery was not lower than 80%. FISH could be used to perform ALK gene rearrangement analysis on the collected NCI-H2228 cells, and EGFR Exon 19 deletion was detected by PCR-based analysis in isolated HCC827 cells. The in vivo feasibility of this technique had been demonstrated in patients with non-small cell lung cancer, breast, colon, and esophageal cancers. CTCs were detected in 13 of 59 blood samples. Tumor microemboli was also detected in three breast cancer samples.

CONCLUSIONS

The technique we developed allowed isolation and characterization of circulating epithelial tumor cells that do not express classical epithelial antigens. This potentially leads to a more accurate enumeration of the number of CTCs and is suitable for application to a broad range of cancers.

[Disseminated and circulating tumor cells in gastrointestinal oncology]

Circulating (CTC) and disseminated tumor cells (DTC) represent two different steps of the metastatic process. As with other types of cancer, the recent development of techniques for the detection of CTC and DTC respectively in the blood and bone marrow of patients generated many results in digestive cancers. However, the interpretation of these results and of the prognostic value of CTC/DTC is often limited by the small cohort size and the heterogeneity of detection methods. The aim of this article is to review the different results and their clinical impact, and discuss the possible use of CTC and DTC as new biomarkers. First of all, it is important to take into account the variability of epithelial markers used for the initial stage of immunoselection of CTC/DTC as well as that of molecular or cytological markers used for the second stage of detection. In esophageal, gastric, pancreatic and hepatocellular carcinomas, and in the ileal and pancreatic neuroendocrine tumors, some studies showed a correlation between the detection of CTC and/or DTC and a clinical pejorative course, whether these tumors were at localized or metastatic stages. On colorectal cancer in the adjuvant setting, a recent meta-analysis showed an association between the detection of CTC in peripheral blood and disease-free survival or overall survival. These results are consistent with those of a study that identified detection of CTC as a prognostic factor for relapse in stage II. This last study concluded that it was necessary to achieve long-term evaluation of CTC as a biomarker to guide the decisions of chemotherapy for stage II. In metastatic colorectal cancer, the FDA approved in 2007 the use of pretherapeutic levels of CTC and its variations per-treatment, determined by CellSearch(®) technology, as a tool in treatments management. However, the modalities of this monitoring have to be specified and clinical benefit or the cost-effectiveness of a treatment based on this new biomarker has to be evaluated. Finally, the qualitative and quantitative monitoring of CTC could be a non-invasive tool to monitor changes in tumor biology throughout the disease, and thereby improve the understanding of the processes of dissemination and therapeutic resistance.

Neutrophils promote liver metastasis via Mac-1-mediated interactions with circulating tumor cells

Although circulating neutrophils are associated with distant metastasis and poor outcome in a number of epithelial malignancies, it remains unclear whether neutrophils play an active causal role in the metastatic cascade. Using in vivo models of metastasis, we found that neutrophils promote cancer cell adhesion within liver sinusoids and, thereby, influence metastasis. Neutrophil depletion before cancer cell inoculation resulted in a decreased number of gross metastases in an intrasplenic model of liver metastasis. This effect was reversed when inflamed neutrophils were co-inoculated with cancer cells. In addition, early adhesion within liver sinusoids was inhibited in the absence of neutrophils and partially restored with a short perfusion of isolated activated neutrophils. Intravital microscopy showed that cancer cells adhered directly on top of arrested neutrophils, indicating that neutrophils may act as a bridge to facilitate interactions between cancer cells and the liver parenchyma. The adhesion of lipopolysaccharide-activated neutrophils to cancer cells was mediated by neutrophil Mac-1/ICAM-1. Our findings, therefore, show a novel role for neutrophils in the early adhesive steps of liver metastasis.

Metastasis: recent discoveries and novel perioperative treatment strategies with particular interest in the hemostatic compound desmopressin

Metastatic disease is responsible for most of cancer lethality. A main obstacle for therapy of advanced cancers is that the outcome of metastasis depends on a complex interplay between malignant and host cells. The perioperative period represents an underutilized window of opportunity for cancer treatment where tumor-host interactions can be modulated, reducing the risk of local recurrences and distant metastases. Blood-saving agents are attractive compounds to be administered during tumor surgery. Desmopressin (DDAVP) is a safe and convenient hemostatic peptide with proved antimetastastic properties in experimental models and veterinary clinical trials. The compound seems to induce a dual angiostatic and antimetastatic effect, breaking the cooperative function of cancer cells and endothelial cells during residual tumor progression. DDAVP is therefore an interesting lead compound to develop novel synthetic peptide analogs with enhanced antitumor properties.

Prognostic and predictive roles for circulating biomarkers in gastrointestinal cancer

Circulating tumor cells (CTCs) and circulating free DNA (cfDNA) have been studied as promising prognostic and predictive tumor-derived biomarkers in the bloodstream of patients with gastrointestinal malignancies because they may be an alternative noninvasive tool to tumor tissue biopsies. Quantification and molecular characterization of CTCs and cfDNA may provide additional insights into cancer biology, potentially revealing novel targets to individualize cancer care. The present article aims to review the biology and current methods to assess CTCs and cfDNA, and the efforts to establish both tumor-derived biomarkers as prognostic and predictive factors in esophageal, gastric and colorectal cancer.

Clinical significance of stanniocalcin-1 detected in peripheral blood and bone marrow of esophageal squamous cell carcinoma patients

Background

Stanniocalcin-1 (STC-1) is a potential marker of disseminated tumor cells (DTCs). The aim of this study was to examine STC-1 expression in peripheral blood (PB) and bone marrow (BM) of esophageal squamous cell carcinoma (ESCC) patients, and to evaluate its clinical significance.

Methods

A total of 85 ESCC patients treated with radical resection were enrolled in this study. Immunohistochemistry was used to detect STC-1 protein expression in ESCC tissues. Nested RT-PCR was used to detect STC-1 mRNA expression in PB and BM.

Results

There were 71 cases (83.5%) showed a higher level of STC-1 protein expression in tumor tissues than in adjacent normal tissues (P < 0.001). Furthermore, the frequencies of STC-1 mRNA expression detected in PB and BM were 37.6% (32/85) and 21.2% (18/85), respectively, and together increased sensitivity to 48.2% (41/85), which was much higher than that in patients with benign esophageal disease (5.0%, 2/40, P < 0.001). In addition, STC-1 mRNA expression either in PB or BM was correlated with lymph metastasis, advanced stage and adverse 2-year progression free survival (PFS). In a multivariate analysis using the Cox proportional hazard model, STC-1 expression in PB and/or BM was an independent unfavorable prognostic factor for ESCC, apart from lymph metastasis and clinical stage.

Conclusions

STC-1 mRNA expression is a reliable marker for detection of DTCs in PB and BM of ESCC patients, and STC-1-positive DTCs may be a promising tool for diagnosis and prognosis assessment in ESCC.

Risks and benefits of thoracic epidural anaesthesia

Thoracic epidural anaesthesia (TEA) reduces cardiac and splanchnic sympathetic activity and thereby influences perioperative function of vital organ systems. A recent meta-analysis suggested that TEA decreased postoperative cardiac morbidity and mortality. TEA appears to ameliorate gut injury in major surgery as long as the systemic haemodynamic effects of TEA are adequately controlled. The functional benefit in fast-track and laparoscopic surgery needs to be clarified. Better pain control with TEA is established in a wide range of surgical procedures. In a setting of advanced surgical techniques, fast-track regimens and a low overall event rate, the number needed to treat to prevent one death by TEA is high. The risk of harm by TEA is even lower, and other methods used to control perioperative pain and stress response also carry specific risks. To optimize the risk-benefit balance of TEA, safe time intervals regarding the use of concomitant anticoagulants and consideration of reduced renal function impairing their elimination must be observed. Infection is a rare complication and is associated with better prognosis. Close monitoring and a predefined algorithm for the diagnosis and treatment of spinal compression or infection are crucial to ensure patient safety with TEA. The risk-benefit balance of analgesia by TEA is favourable and should foster clinical use.

Organ-specific markers in circulating tumor cell screening: an early indicator of metastasis-capable malignancy

Circulating tumor cells (CTCs) represent an important biological link in the spread of primary solid tumors to the metastatic disease responsible for most cancer mortality. Their detection in the peripheral blood of patients with many different carcinomas has shown that tumor-cell dissemination can proceed at an early stage of tumor development and their presence is associated with poor clinical outcomes, particularly in metastatic disease. In this article we describe how the increasingly sensitive isolation and detailed molecular characterization of CTCs has greatly improved our understanding of metastatic proliferation. We focus on how CTC detection and knowledge of the molecular architecture of these cells can serve as biomarkers to signal metastasis-capable disseminating cells and predict therapy-specific response. This has marked clinical utility for improved selection of systemic therapies to the individual needs of a cancer patient, real-time monitoring of metastatic disease treatments and the development of new targeted therapies.

Disseminated and circulating tumor cells in gastrointestinal oncology

Circulating (CTCs) and disseminated tumor cells (DTCs) are two different steps in the metastatic process. Several recent techniques have allowed detection of these cells in patients, and have generated many results using different isolation techniques in small cohorts. Herein, we review the detection results and their clinical consequence in esophageal, gastric, pancreatic, colorectal, and liver carcinomas, and discuss their possible applications as new biomarkers.

Negative enrichment by immunomagnetic nanobeads for unbiased characterization of circulating tumor cells from peripheral blood of cancer patients

BACKGROUND

A limitation of positive selection strategies to enrich for circulating tumor cells (CTCs) is that there might be CTCs with insufficient expression of the surface target marker which may be missed by the procedure. We optimized a method for enrichment, subsequent detection and characterization of CTCs based on depletion of the leukocyte fraction.

METHODS

The 2-step protocol was developed for processing 20 mL blood and based on red blood cell lysis followed by leukocyte depletion. The remaining material was stained with the epithelial markers EpCAM and cytokeratin (CK) 7/8 or for the melanoma marker HMW-MAA/MCSP. CTCs were detected by flow cytometry. CTCs enriched from blood of patients with carcinoma were defined as EpCAM+CK+CD45-. CTCs enriched from blood of patients with melanoma were defined as MCSP+CD45-. One-hundred-sixteen consecutive blood samples from 70 patients with metastatic carcinomas (n = 48) or metastatic melanoma (n = 22) were analyzed.

RESULTS

CTCs were detected in 47 of 84 blood samples (56%) drawn from carcinoma patients, and in 17 of 32 samples (53%) from melanoma patients. CD45-EpCAM-CK+ was detected in pleural effusion specimens, as well as in peripheral blood samples of patients with NSCLC. EpCAM-CK+ cells have been successfully cultured and passaged longer than six months suggesting their neoplastic origin. This was confirmed by CGH. By defining CTCs in carcinoma patients as CD45-CK+ and/or EpCAM+, the detection rate increased to 73% (61/84).

CONCLUSION

Enriching CTCs using CD45 depletion allowed for detection of epithelial cancer cells not displaying the classical phenotype. This potentially leads to a more accurate estimation of the number of CTCs. If detection of CTCs without a classical epithelial phenotype has clinical relevance need to be determined.

Detection of circulating tumor cells: Clinical relevance of a novel metastatic tumor marker

Most cancer-related deaths are caused by the hematogenous spread of cancer cells to distant organs and their subsequent metastasis. During the early stages of the metastatic cascade, cancer cells disseminate from the primary site via the lymphatic vessels and/or by hematogenous routes. Circulating tumor cells (CTCs), cancer cells that have disseminated into the systemic circulation, may be a predictor of poor prognosis in several carcinomas. An understanding of the molecular mechanisms involved in the blood-borne dissemination of cancer cells may help to clarify the process of metastasis and provide a powerful and non-invasive approach for anticancer treatments that are tailored to individual patients.

TTF-1 mRNA-positive circulating tumor cells in the peripheral blood predict poor prognosis in surgically resected non-small cell lung cancer patients

Circulating tumor cells (CTCs) have been identified in peripheral blood of cancer patients, and reproducible detection of CTCs has demonstrated the potential as useful diagnostic and prognostic tools in several cancers. Present study aimed to determine the clinical relevance of CTCs in surgically resected non-small cell lung cancer (NSCLC) patients. CTC status in presurgery and postsurgery peripheral blood samples from 79 surgically resected NSCLC patients was investigated using thyroid transcription factor-1 (TTF-1) and cytokeratin19 (CK19) mRNA markers by nested real-time RT (reverse transcription)-PCR assay. Detection of TTF-1((+))CTCs was found to be specific to NSCLC patients. TTF-1((+))CTCs were detected in 36.1% (22/61) of patients before surgery and in 37.5% (18/48) after surgery. For CK19 mRNA-expressing CTCs (CK19((+))CTCs), the detection rate was 42.6% (26/61) before surgery, and 25.0% (12/48) after surgery. Cases with postsurgery TTF-1((+)) and/or CK19((+))TCs was more associated with disease progression (P=0.004) and shorter disease progression-free survival (P=0.006) as compared to those without postsurgery CTCs. As an individual marker, postsurgery TTF-1((+))CTCs-positive status was more associated with disease progression (P=0.004) and shorter disease progression-free survival (P=0.004) as compared to postsurgery TTF-1((+))CTCs-negative status. Particularly, patients with postsurgery TTF-1((+))CTCs, but not presurgery (Pre((-))Post((+)) cases) showed marked shorter disease progression-free survival than other patients (P<0.001). On the other hand, a CK19((+))CTC status individually did not show significant clinical relevance, and presurgery CK19((+))CTC status did not either. Present study suggests that TTF-1 mRNA-expressing CTCs might be a useful surrogate predictor of disease progression before clinical manifestations are apparent, and that monitoring of TTF-1((+))CTCs status after surgery may be useful for identifying high-risk patients among surgically resected NSCLC cases.

CEA-antigen and SCC-antigen mRNA expression in peripheral blood predict hematogenous recurrence after resection in patients with esophageal cancer

BACKGROUND

Although several studies have suggested an association between circulating tumor cells (CTC) and prognosis after esophageal cancer surgery, large-scale studies are lacking. The aim of this study was to prospectively examine the correlation between CTC and outcome in a large number of patients who underwent esophagectomy.

MATERIALS AND METHODS

A cohort of 244 patients with squamous cell carcinoma of the esophagus who underwent curative surgery between 2002 and 2007 were prospectively analyzed for CTC before surgery and after the thoracic procedure. Reverse transcription-polymerase chain reaction for CEA and SCC antigen mRNA was used to detect cancer cells in the peripheral blood. CTC was defined as positive when at least 1 tumor marker mRNA was detected.

RESULTS

CTC was positive in 34 patients (13.9%) before surgery and in 41 patients (16.8%) after the thoracic procedure. Multivariate analysis identified tumor depth (hazard ratio [HR], 0.439; 95% confidence interval [95% CI], 0.268-0.722; P = 0.0012), lymph node metastasis (HR, 2.467; 95% CI, 1.436-4.237; P = 0.0011), venous invasion (HR, 1.802; 95% CI, 1.082-3.002; P = 0.0236), and CTC status after the thoracic procedure (HR, 1.647; 95% CI, 1.032-2.629; P = 0.0365) as independent prognostic factors of disease-free survival. The rates of hematogenous (P = 0.0222) and local (P = 0.0464) recurrences were significantly higher in patients with CTC(+) after the thoracic procedure than those with CTC(-) after the thoracic procedure. Responders to neoadjuvant chemotherapy showed less lymphatic invasion and a decreased positive CTC rate after the thoracic procedure than nonresponders.

CONCLUSIONS

CTC status after the thoracic procedure is a useful predictor for hematogenous and local recurrences in patients with esophageal cancer.

Long term survival following the detection of circulating tumour cells in head and neck squamous cell carcinoma

BACKGROUND

Techniques for detecting circulating tumor cells in the peripheral blood of patients with head and neck cancers may identify individuals likely to benefit from early systemic treatment.

METHODS

Reconstruction experiments were used to optimise immunomagnetic enrichment and RT-PCR detection of circulating tumor cells using four markers (ELF3, CK19, EGFR and EphB4). This method was then tested in a pilot study using samples from 16 patients with advanced head and neck carcinomas.

RESULTS

Seven patients were positive for circulating tumour cells both prior to and after surgery, 4 patients were positive prior to but not after surgery, 3 patients were positive after but not prior to surgery and 2 patients were negative. Two patients tested positive for circulating cells but there was no other evidence of tumor spread. Given this patient cohort had mostly advanced disease, as expected the detection of circulating tumour cells was not associated with significant differences in overall or disease free survival.

CONCLUSION

For the first time, we show that almost all patients with advanced head and neck cancers have circulating cells at the time of surgery. The clinical application of techniques for detection of spreading disease, such as the immunomagnetic enrichment RT-PCR analysis used in this study, should be explored further.

Circulating tumor cells in gastrointestinal malignancies: current techniques and clinical implications

Since their introduction more than 50 years by Engell, circulating tumor cells (CTCs) have been evaluated in cancer patients and their detection has been correlated with clinical outcome, in esophageal, gastric, and colorectal cancer. With the availability of refined technologies, the identification of CTCs from peripheral blood is emerging as a useful tool for the detection of malignancy, monitoring disease progression, and measuring response to therapy. However, increasing evidence suggests a variety of factors to be responsible for disease progression. The analysis of a single CTC marker is therefore unlikely to accurately predict progression of disease with sufficient resolution and reproducibility. Here we discuss the current concept of CTCs, summarize the available techniques for their detection and characterization, and aim to provide a comprehensive update on the clinical implications of CTCs in gastrointestinal (GI) malignancies.

Detection of survivin-expressing circulating cancer cells in the peripheral blood of patients with esophageal squamous cell carcinoma and its clinical significance

We previously demonstrated that the detection of circulating cancer cells (CCC) expressing survivin mRNA could provide valuable information for predicting recurrence in patients with breast, lung, gastric and colorectal carcinoma. The purpose of this study is to investigate whether the detection of survivin-expressing CCC in the peripheral blood is also useful for predicting recurrence in patients with esophageal squamous cell carcinoma (ESCC). Blood samples obtained from 108 ESCC patients and 75 healthy volunteers were quantitatively investigated by a technique that detected reverse transcription-polymerase chain reaction products based on a hybridization-enzyme linked immunosorbent essay. Not all of the patients were available for the follow-up study. Only 48 patients who were treated with similar adjuvant therapy regimens were available and followed-up for 33 months after the initial assay test. Survivin-expressing CCC were detected in 51 (47.2%) patients. The presence of survivin-expressing CCC was found to be significantly associated with depth of invasion, vascular invasion, nodal status, and disease stages (P = 0.032, 0.019, 0.018, and 0.001, respectively). During the follow-up period, patients who had positive survivin expressions had a higher relapse rate and a shorter survival time than those who had negative survivin expressions (P = 0.002 and 0.016, respectively). Examination of survivin-expressing CCC could provide valuable information in the prediction of haematogenous recurrence as well as in the prognosis of ESCC.

Revisiting perioperative chemotherapy: the critical importance of targeting residual cancer prior to wound healing

BACKGROUND

Scientists and physicians have long noted similarities between the general behavior of a cancerous tumor and the physiological process of wound healing. But it may be during metastasis that the parallels between cancer and wound healing are most pronounced. And more particularly and for the reasons detailed in this paper, any cancer remaining after the removal of a solid tumor, whether found in micrometastatic deposits in the stroma or within the circulation, may be heavily dependent on wound healing pathways for its further survival and proliferation.

DISCUSSION

If cancer cells can hijack the wound healing process to facilitate their metastatic spread and survival, then the period immediately after surgery may be a particularly vulnerable period of time for the host, as wound healing pathways are activated and amplified after the primary tumor is removed. Given that we often wait 30 days or more after surgical removal of the primary tumor before initiating adjuvant chemotherapy to allow time for the wound to heal, this paper challenges the wisdom of that clinical paradigm, providing a theoretical rationale for administering therapy during the perioperative period.

SUMMARY

Waiting for wound healing to occur before initiating adjuvant therapies may be seriously compromising their effectiveness, and patients subsequently rendered incurable as a result of this wait. Clinical trials to establish the safety and effectiveness of administering adjuvant therapies perioperatively are needed. These therapies should target not only the residual cancer cells, but also the wound healing pathway utilized by these cells to proliferate and metastasize.

Detection, clinical relevance and specific biological properties of disseminating tumour cells

Most cancer deaths are caused by haematogenous metastatic spread and subsequent growth of tumour cells at distant organs. Disseminating tumour cells present in the peripheral blood and bone marrow can now be detected and characterized at the single-cell level. These cells are highly relevant to the study of the biology of early metastatic spread and provide a diagnostic source in patients with overt metastases. Here we review the evidence that disseminating tumour cells have a variety of uses for understanding tumour biology and improving cancer treatment.