Parallel Evaluation of Circulating Tumor DNA and Circulating Tumor Cells in Metastatic Colorectal Cancer

Background

Tissue biopsy is the gold standard for tumor genotyping, but it is an invasive procedure providing a single snapshot into tumor heterogeneity. Liquid biopsy approaches, encompassing the analysis of circulating tumor DNA (ctDNA) or circulating tumor cells (CTCs), have been proposed as an alternative, with the potential of providing a comprehensive portrait of the tumor molecular landscape. In metastatic colorectal cancer (mCRC), both CTCs and ctDNA analysis have been investigated, but comparative analyses are limited.

循环肿瘤细胞与转移性前列腺癌患者预后关系的Meta分析

目的 通过Meta分析系统评价循环肿瘤细胞（circulating tumor cells, CTCs）与转移性前列腺癌患者的预后关系。方法 检索PubMed、EMbase、Cochrane图书馆、中国期刊全文数据库（CNKI）及中国生物医学文献数据库（CBM）等,收集患者血液中CTCs数量与前列腺癌Gleason评分0~10级的前列腺癌患者预后相关的研究。以总生存期（OS）为观察终点,采用Review Manager 5.3进行Meta分析。结果 共有10篇英文文献纳入Meta分析,结果显示CTCs阳性组较CTCs阴性组在总生存期（OS）上预后差（HR=2.47, 95%CI: 2.02~3.02, P<0.00001）,根据检测时间与检测方法进行亚组分析,CTCs阳性组比CTCs阴性组患者预后差。同时分析结果还提示CTCs阳性与前列腺癌Gleason评分呈正相关（OR=2.23, 95%CI: 1.41~3.53,P<0.04）。与前列腺癌特异性抗原（PSA）水平、是否有骨外多发转移均无相关性。结论 外周血CTCs阳性是转移性前列腺癌患者预后的风险因素,且与检测时间、检查方法无关。     

循环肿瘤细胞联合血清CA153检测在转移性乳腺癌中临床意义

摘 要：［目的］ 探讨循环肿瘤细胞(CTCs)和肿瘤标志物CA153检测在转移性乳腺癌(MBC)中临床意义。［方法］ 选取2016年5月至2018年5月诊治的80例转移性乳腺癌患者作为研究对象,患者均给予化疗、靶向或内分泌治疗等,检测治疗前后CTCs和肿瘤标志物CA153水平,分析其与疗效及预后的关系。［结果］ MBC治疗后CTCs阳性率（37.50%）明显低于治疗前（61.25%）（P<0.05）;治疗后糖类抗原153（CA153）低于治疗前,但差异无统计学意义（P>0.05）。80例MBC患者治疗后达到完全或部分缓解30例(37.5%),稳定27例(33.75%),无效进展23例(28.75%)。患者病程中CTCs数目的改变与病情的转归相关。化疗后CTCs数目不变或下降的病例,预后较好;化疗后CTCs数目上升的病例预后差。［结论］ 循环肿瘤细胞联合血清CA153检测能够预测疗效和判断预后。循环肿瘤细胞在监测转移性乳腺癌疗效和预后具有一定的临床价值。     

Detection of Circulating Tumor Cells in Breast Cancer Patients:Prognostic Predictive Role

A determination of circulating tumor cell (CTC) effectiveness for prediction of progression-free survival(PFS) and overall survival (OS) was conducted as an adjunct to standard treatment of care in breast cancermanagement. Between November 2008 and March 2009, 22 metastatic and 12 early stage breast carcinomapatients, admitted to Ankara Oncology Training and Research Hospital, were included in this prospective trial.Patients’ characteristics, treatment schedules and survival data were evaluated. CTC was detected twice byCellSearch method before and 9-12 weeks after the initiation of chemotherapy. A cut-off value equal or greaterthan 5 cells per 7.5 ml blood sample was considered positive. All patients were female. Median ages were 48.0(range: 29-65) and 52.5 (range: 35-66) in early stage and metastatic subgroups, respectively. CTC was positivein 3 (13.6%) patients before chemotherapy and 6 (27.3%) patients during chemotherapy in the metastaticsubgroup whereas positive in only one patient in the early stage subgroup before and during chemotherapy.The median follow-up was 22.0 (range: 21-23) and 19.0 (range: 5-23) months in the early stage and metastaticgroups, respectively. In the metastatic group, both median PFS and OS were significantly shorter in any timeCTC positive patients compared to CTC negative patients (PFS: 4.0 vs 14.0 months, Log-Rank p=0.013; andOS: 8.0 months vs. 20.5 months, Log-Rank p<0.001). OS was affected from multiple visceral metastatic sites(p=0.055) and higher grade (p=0.044) besides CTC positivity (log rank p<0.001). Radiological response ofchemotherapy was also correlated with better survival (p<0.001). As a result, CTC positivity was confirmed asa prospective marker even in a small patient population, in this single center study. Measurement of CTC byCellSearch method in metastatic breast carcinoma cases may allow indications of early risk of relapse or deathwith even as few as two measurements during a chemotherapy program, but this finding should be confirmedwith prospective trials in larger study populations.     

Detection of HER2-positive Circulating Tumor Cells Using the LiquidBiopsy System in Breast Cancer

Background

Most previous studies of circulating tumor cells (CTCs) are based on the CellSearch platform, but CellSearch has a number of limitations. This study aimed to use the LiquidBiopsy system and immunofluorescence to test the human epidermal growth factor receptor 2 (HER2) status of CTCs in patients with breast cancer.

Circulating Tumor Cells in the Management of Breast Cancer

Most deaths from breast cancer are from metastatic disease. Tests that predict an individual's risk of developing metastatic disease could be useful. There is growing evidence that circulating tumor cells (CTC) could help predict recurrence and effectiveness of therapy. However, there are unresolved issues with CTC detection methods and their implementation in the community. The utility of CTC testing in the management of breast cancer is unclear based on current studies. This article reviews the role of CTC testing in the management of early and metastatic breast cancer.     

A Randomized Phase II Trial Investigating the Effect of Platelet Function Inhibition on Circulating Tumor Cells in Patients With Metastatic Breast Cancer

BackgroundBlockade of platelet activation and aggregation can inhibit metastasis in preclinical models and is associated with cancer prevention. To test whether disruption of platelet function with clopidogrel and aspirin would decrease the number of circulating tumor cells (CTCs) in patients with metastatic breast cancer, a randomized phase II study was performed.MethodsPatients with metastatic breast cancer who were not currently receiving cytotoxic chemotherapy were eligible. Patients were randomized to receive either clopidogrel and aspirin or to a control group receiving no treatment. Phlebotomy was performed at baseline, at 2 and 4 weeks, and monthly thereafter to obtain specimens to assess CTC, platelet aggregation, and thrombin activity. The primary end point was the proportion of patients with detectable CTCs at 1 month.ResultsForty-eight patients were enrolled and 42 were evaluable at 1 month. Baseline CTC numbers were ≥ 5 in 13% and ≥ 1 in 65% of patients. Despite adequate platelet function inhibition in the treatment group, the proportion of patients with detectable CTCs was similar between the clopidogrel/aspirin and control groups at baseline (P = .21) and 4 weeks (P = .75), showing no treatment effect. Measured endogenous thrombin potential did not correlate with CTC number. No bleeding-related serious adverse events (SAEs) occurred.ConclusionThe baseline CTC numbers were lower than expected, decreasing the ability to detect an impact of platelet inhibition on CTCs. Clopidogrel and aspirin were well tolerated. Future studies evaluating the potential therapeutic role of antiplatelet therapy in breast cancer remain of interest, and they may be informed by these results.     

Role of Circulating Tumor Cells in Metastatic Colorectal Cancer: Clinical Challenges and Opportunities

Circulating tumour cells (CTCs) have been presumed critical to the metastatic process since 1800. These epithelial cells are disseminated from the primary or metastatic tumor site and can be identified in the peripheral blood of patients. Nowadays, technical advances have rendered it easier to reproducibly and repeatedly sample this population of cells with an acceptable degree of accuracy. Therefore, these cells could become an attractive surrogate for phenotypic and genotypic markers in correlation with the development of molecular targeted therapies. In metastatic colorectal cancer several prospective studies have demonstrated the independent prognostic significance of CTCs and identified the number of CTCs before and during treatment as a predictor for overall survival and disease free survival. However, the underlying molecular characteristics of CTCs associated with outcome remain largely unknown. In this review, the role of CTCs in metastatic colorectal cancer is discussed. The variety of assays that can be used for enrichment and detection steps in CTC detection will be described and the clinical utility of these cells for assessing prognosis and monitoring response to therapy will be analyzed. We will also address the shortcomings of current detection methods that fail to identify a mesenchymal subgroup of CTCs, and briefly address how characterization of these cells can help elucidate the biology of cancer metastases.     

Prognostic Significance of Circulating Tumor Cells and SerumCA15-3 Levels in Metastatic Breast Cancer,Single CenterExperience,Preliminary Results

Background: Breast cancer is the second leading cancer causing death in women. Circulating tumor cellsare among the prognostic factors while tumor markers are of diagnostic value and can be used for follow-up.The aim of this study was to investigate the correlation between the prognostic significance of the serum CA15-3levels, number of circulating tumor cells and histopathological tumor factors. Materials and Methods: Thirtypatients recently diagnosed with breast cancer were included in the study. Number of circulating tumor cells andserum CA15-3 level were assessed when metastasis was detected and diagnostic value was assessed. Presence ofassociations with estrogen and progesterone receptors, c-erbB2, Ki-67 proliferation index and histological gradewere also evaluated. Results: Median overall survival of the patients with serum CA15-3 levels of >108 ng/dlwas 19 months whereas for those with a low serum level it was 62 months. Median overall survival for CTC≥5vs CTCConclusions: Prognostic significance of the CTC count and CA15-3 levels in metastaticbreast cancer patients was demonstrated.     

Prognostic Value of Circulating Tumor Cells According to Immunohistochemically Defined Molecular Subtypes in Advanced Breast Cancer

BackgroundBreast cancer is a heterogeneous disease. Circulating tumor cell (CTC) enumeration might be useful to identify different risk categories within each molecular subtype.MethodsWe retrospectively analyzed 203 consecutive patients with metastatic breast cancer with baseline CTC enumeration performed with CellSearch (Veridex Corp, Warren, NJ) between March 2005 and July 2011. Patients were categorized into 3 prognostic groups based on the number of CTCs (0, 1-4, and ≥ 5) and into 5 categories based on tumor biological characteristics: luminal-A (estrogen receptor [ER] and progesterone receptor [PR] > 1%, grade 1/2, human epidermal growth factor 2 [HER2]-negative [HER2^?], Ki67 value < 14%); luminal-B (ER and/or PR > 1%, grade 3, HER2^?, Ki67 value > 14%); luminal-B HER2–positive [HER2⁺] (ER and/or PR > 1%, any grade, HER2⁺, Ki-67 value any); HER2⁺ (HER2 overexpressed/fluorescence in situ hybridization [FISH] amplified, ER and PR absent); triple negative (TN) (ER and PR 0%, HER2 not overexpressed/FISH not amplified).ResultsMedian age was 57 years (range 31-78 years). Twenty-seven patients (13.3%) had luminal-A category, 105 (51.7%) patients had luminal-B, 29 (14.3%) patients had luminal-B HER2⁺, 24 patients (11.8%) had HER2⁺, and 18 patients (8.9%) had TN. CTCs were mostly found in patients with luminal-A/luminal-B HER2^? subtype. At multivariable analysis, CTC count was a significant predictive factor for overall survival (OS) in all molecular subtypes (log-rank P < .01). Patients with 0 CTCs/7.5 mL blood and all subtypes, except HER2⁺, seem to perform better compared with other categories.ConclusionThese findings confirm CTCs as an important prognostic factor for metastatic breast cancer in all molecular subtypes. Larger studies could help identify metastatic breast cancer subgroups in which CTC analysis would be particularly useful.     

早期乳腺癌hMAM mRNA阳性循环肿瘤细胞检测及其临床意义

 目的 研究早期乳腺癌hMAM mRNA阳性循环肿瘤细胞检测的临床意义。 方法 巢式RT PCR检测50例早期乳腺癌患者术后辅助治疗前外周血hMAM mRNA阳性细胞,随访。24例乳腺良性疾病患者和20例健康体检志愿者作对照。 结果 早期乳腺癌患者术后辅助治疗前外周血有核细胞hMAM mRNA阳性率26.0%,与良性乳腺疾病患者（4.2%）、健康体检志愿者（0%）比较,差异有统计学意义(分别为P=0.025、P=0.012);其hMAM mRNA阳性率与癌组织HER2过表达相关（P=0.037）;13例阳性患者中8例（61.5%）随访出现复发转移（P=0.004）,中位无瘤生存期明显降低（P=0.002）。 结论 hMAM mRNA是检测乳腺癌循环肿瘤细胞较为理想的分子标记物。早期乳腺癌患者术后辅助治疗前hMAM mRNA阳性循环肿瘤细胞检测,可能是预测复发转移和预后不良的辅助指标。     

Enumeration of Circulating Tumor Cells in the Blood of Breast Cancer Patients After Filtration Enrichment: Correlation with Disease Stage

The biological and clinical significance of circulating tumor cells (CTC) in the peripheral blood of breast cancer patients is not known. To study this question, we used a direct visualization assay to correlate the number of CTC with disease stage and progression. The CTC were enriched from the nucleated cell fraction by filtration and enumerated visually following immunostaining with anti-cytokeratin 8 (CK8) antibody CAM 5.2. In mixing experiments, we achieved a limit of detection of 5 MCF7 cells per 5 ml of blood or 5 x 10(7) peripheral blood leukocytes (PBL). We did not detect CTC in any control subjects (0/20). In 131 breast cancer patients, we found a higher incidence of CTC in patients with distant metastatic 36/51 (71%) than those with node-positive 17/36 (47%) (p = 0.026), or node-negative 17/44 (39%) (p = 0.001) disease. The distribution of the highest numbers of CTC observed in individual patients by repeated sampling over time ranged from 1 to 700 per 5 ml of blood with a trend toward higher numbers in those with distant metastases. In comparison with previous studies of equal specificity, based on a similar absence of CTC in controls, we report a higher incidence of CTC in node-negative and node-positive patients, suggesting a more frequent detection of CTC by our approach. This higher incidence was achieved, in part, by repeated sampling of our study population over time. Our results support the concept that CTC can be detected and enumerated in peripheral blood and that this minimally invasive assay merits further evaluation as a potential prognostic indicator and marker of disease progression.     

The Evolving Role of Circulating Tumor Cells in the Personalized Management of Breast Cancer: From Enumeration to Molecular Characterization

Circulating tumor cells (CTCs) represent tumor cells in the blood stream dislodged from the primary tumor. The presence of CTCs in the bloodstream provides a unique opportunity to sample cancer tissue by means of a relatively less-invasive “liquid biopsy.” Over the past decade, there has been a tremendous increase in the amount of research examining the potential clinical utility of CTCs in the management of cancer. A number of techniques to refine the sensitivity and range of CTC assays are also in development. In this article, we review the recent developments in the current and potential clinical applications of CTCs in breast cancer. CTC enumeration already has an established role as a prognostic biomarker in metastatic breast cancer, whereas molecular characterization of CTCs can serve as a potential predictive biomarker for therapy selection, pharmacodynamic evaluation, and identification of novel actionable targets for novel therapies. The role of CTCs in breast cancer screening and detection of recurrence is currently limited. Further development in techniques will be pivotal in enhancing the broad applicability of CTCs and advancing the field of personalized breast cancer therapy.     

肺癌循环肿瘤细胞的临床意义

循环肿瘤细胞(circulating tumor cells,CTCs)是指自发地或因诊疗操作由实体瘤或转移灶释放入血的恶性肿瘤细胞.目前,CTCs在恶性肿瘤诊断、分期、评效、治疗、预后中的意义及其富集分离、检测技术已成为研究热点.     

Analysis of the Prognostic Significance of Circulating Tumor DNA in Metastatic Castrate Resistant Prostate Cancer

BackgroundThere has been considerable interest in ctDNA next generation sequencing platforms to assess genomic alterations in mCRPC given its accessibility and identification of temporal genomic data.Patientsand MethodsIn this retrospective analysis, we analyzed 63 patients who underwent ctDNA genomic profiling during their mCRPC disease course using a CLIA-certified commercial assay. The primary objective was to assess the feasibility of commercial ctDNA analysis in a real world mCRPC cohort. Key secondary objectives included assessment of the landscape of pathogenic ctDNA alterations and the prognostic significance of ctDNA detection on overall survival (OS).ResultsAmong the cohort, at the time of ctDNA collection, median age was 70 years, and 47.6% (N = 30/63) had bone-only metastases. ctDNA was detected in the majority of patients with at least 1 pathogenic alteration detected in 90.5% (N = 57/63) of individuals. The most common alterations detected were in AR, TP53, and PIK3CA. Actionable alterations with FDA-approved therapies were found in 15.8% (N = 10) of the cohort. The presence of ≤ 1 versus > 1 alteration on ctDNA analysis was strongly associated with inferior OS with a median OS of 26.1 versus 8.8 months, respectively (HR = 7.0, 95% CI, 2.2-23.1, P < .001). In multivariate analysis, the number of detected alterations remained a significant predictor for OS. Lastly, there was weak correlation between Prostate-Specific Antigen (PSA), and ctDNA characteristics.ConclusionctDNA is a viable next generation sequencing (NGS) platform in mCRPC and can be utilized to identify actionable alterations. The presence and extent of ctDNA alterations appear to be prognostic of OS in mCRPC.     

乳腺癌循环肿瘤细胞研究及其检测进展

乳腺癌是女性发生率最高的恶性肿瘤之一,其引起死亡的主要原因是乳腺癌的复发转移.转移灶的形成是一个连续复杂的过程,从原发灶生长的早期即已开始.肿瘤细胞进入血液循环是乳腺癌发生转移的基础.经过多种复杂机制最终形成转移灶.因此,检测循环肿瘤细胞(CTC)对预测转移有重要作用.由于外周血中CTC数量稀少,增加了其检测的难度.目前对CTC的检测主要分为基于抗体的技术、核酸技术以及联合检测、系统检测等方式,随着试验方法的改进和新技术的不断出现,CTC检测的敏感度和特异性有较大提高.然而缺乏高特异性的标志物仍是CTC检测面临的最大问题.乳腺癌患者CTC水平与肿瘤的分期相关,其水平的升高提示有更高转移的可能.预示患者的预后较差.与传统的组织学及影像学检查相比,CTC检测有更高的可重复性和敏感度,并能更早地提供预后信息.与骨髓微转移肿瘤细胞检测相比,CTC检测具有创伤小、可连续多次检测等特点.CTC检测更重要的意义是能够帮助指导临床个体化治疗方案的制定.通过对CTC连续的检测可以及早地评估治疗效果,据此及时转变为更有效的治疗方案,提高患者的生存率.本文对乳腺癌循环肿瘤细胞的研究、检测技术和临床应用的新进展进行综述.