循环肿瘤细胞检测在胃癌中的临床应用

循环肿瘤细胞（CTC）为存在于肿瘤患者外周血的一类特殊细胞,目前 CTC 检测已应用于胃癌患者生存期预测、术后复发的检测及个体化治疗指导等方面。随着研究的不断深入,CTC 将为胃癌的综合治疗提供新的帮助。     

循环肿瘤细胞应用于肿瘤临床的研究进展

循环肿瘤细胞(circulating tumor cells,CTC)是指存在于肿瘤患者的外周血中能够逃离宿主的免疫杀伤而存活下来的肿瘤细胞。CTC在肿瘤的进展、转移过程中起着重要作用。虽然目前CTC检测技术并未成熟,不同实验室间未形成统一的标准,但是CTC应用于临床作为肿瘤独立的预后指标、监测治疗反应及监测肿瘤分子水平变化指导个体化治疗中,逐渐显现其优势。本文主要就这三方面进行综述。     

循环肿瘤细胞与肺癌

循环肿瘤细胞(CTC)与肿瘤转移有明显的相关性,CTC检测有助于指导肿瘤治疗,为判断预后、预测疗效提供可靠依据.CTC与非小细胞肺癌的分期及远处转移相关.CTC数量变化与非小细胞肺癌患者化放疗疗效及预后有关.小细胞肺癌中CTC检出率和数量均明显高于其他肿瘤,与其分期及化疗疗效有关.CTC有望用于指导肺癌个体化治疗.初步研究结果提示可用CTC来动态了解肺癌患者分子靶向药物治疗过程中耐药肿瘤细胞的出现.     

循环肿瘤细胞及循环肿瘤DNA检测在乳腺癌中的研究进展

乳腺癌是中国女性最常见的癌症,其早期检测、个体化治疗及实时疾病监测一直是科研及临床工作者关注的重点。癌症患者血液中循环肿瘤细胞(CTC)和循环肿瘤DNA(ctDNA)的检测微创、简便,易实时获取信息。目前,有关CTC富集鉴定方法多种多样,CTC及ctDNA检测的敏感度和特异度较前有所提高,未来研究面临的最大挑战为肿瘤细胞特异性标志物的开发以及ctDNA临床意义的研究。CTC及ctDNA在基础研究、检测方法、CTC培养、早期肿瘤检测、个体化治疗及临床预后等方面的研究均有开展。笔者对乳腺癌CTC及ctDNA的研究进展作一总结。     

循环肿瘤细胞检测在非小细胞肺癌中的应用

循环肿瘤细胞（CTC）是非小细胞肺癌（NSCLC）发生复发转移的重要原因。随着检测技术的不断发展,近期研究结果提示,CTC 水平不仅可以用来判断肿瘤临床分期、评估患者预后及治疗反应,还可以用于早期 NSCLC 的风险评估。另外,作为一种非侵入性的“液体活检”,CTC 检测能反映原发肿瘤的分子生物学及遗传学特征,有助于患者获得最佳的个体化治疗。     

循环肿瘤细胞在非小细胞肺癌临床中的应用

研究显示非小细胞肺癌(NSCLC)患者外周血中的循环肿瘤细胞(CTC)携带有肺癌组织特异性抗原或基因特征.检测CTC变化可以评估肺癌的治疗疗效,预测肿瘤的复发、转移及预后.实时动态监测CTC基因分型变化,还可为药物敏感性和耐药机制的研究及NSCLC的个体化治疗提供可靠的依据.     

循环肿瘤细胞研究进展

肿瘤转移是导致肿瘤患者死亡的主要原因之一，相同的治疗方案在同一肿瘤患者之间的疗效差异很大，造成这一现象的原因是恶性肿瘤之间的分子分型存在差异。随着精准医疗时代的到来，循环肿瘤细胞（CTC）检测技术应运而生，人类对恶性肿瘤的检测达到单细胞水平。与传统影像学检查、病理学检查及肿瘤标志物等相比，具有无创、多次、实时获取及整体性等优点；在疗效评估、个体化治疗、预后监测、肿瘤筛查等方面具有独特优势。作者概述常见CTC检测技术的特点及其临床应用现状，为临床提供参考。     

循环肿瘤细胞检测及其临床应用

循环肿瘤细胞(CTC)与恶性肿瘤的发生发展密切相关.目前检测CTC的方法有逆转录聚合酶链反应、免疫磁珠富集检测法等.检测CTC有助于发现早期肿瘤患者的微转移、重新确定临床分期,监测术后或者放化疗后患者肿瘤复发与转移,评估预后,选择个体化的治疗策略.     

循环肿瘤细胞在非小细胞肺癌个体化诊疗中应用的研究进展

非小细胞肺癌(non-small cell lung cancer,NSCLC)是发病率及病死率最高的恶性肿瘤,确诊时大多数NSCLC患者已到疾病晚期,导致患者5年生存率低.随着肿瘤个体化治疗的进展,早期诊断以及对患者病情实时监测尤为重要.循环肿瘤细胞(circulating tumor cell,CTC)作为肿瘤血源性转移的生物学标志物之一,是“液体活检”的重要指标,可用于肿瘤患者实时动态监测.检测CTC有助于早期发现NSCLC微转移、重新确定临床分期、实时监测抗肿瘤治疗疗效、评估预后、制定个体化的治疗策略,不仅如此,对其进一步分子鉴定有助于阐明肿瘤的生物学进程及转移机制.然而,由于检测标准不统一、检测阳性率低等多种因素,现阶段CTC仍较难应用到临床工作中.本文对CTC的发展历程及其在NSCLC诊断、治疗及预后等方面的研究新近进展作一综述.     

循环肿瘤细胞检测技术

循环肿瘤细胞(CTC)检测在肿瘤患者的实时个体化医疗中具有独特的优势.外周血中CTC稀少而又异质,这成为CTC研究的主要技术挑战.CTC检测技术往往首先利用细胞的物理性质或生物学特性等分离富集CTC,再进行基因型或表型分析等以计数CTC或鉴定其分子特征.单细胞分子分析的进展使CTC检测能够提供更准确全面的信息.CTC侵袭转移时上皮间质转化和聚集成簇等生物进程是促进CTC检测的临床应用需要考虑的问题.     

Circulating tumour cells as a predictive factor for response to systemic chemotherapy in patients with advanced colorectal cancer

Circulating tumour cells (CTC) can be traced in patients with different types of cancer. The aim of this study was to detect CTC in patients with advanced colorectal cancer and whether CTC are still detectable after systemic chemotherapy. Blood from 34 patients with advanced colorectal cancer was analysed for the presence of CTC before chemotherapy was given and after 3 months. Eleven patients demonstrated a tumour remission after chemotherapy. In 6 cases CTC were detectable before but not after initiation of chemotherapy. Ten patients demonstrated a progression. In 5 cases CTC were detected before and after chemotherapy. Our data suggest that the detection of CTC will help to identify patients responding to chemotherapy or with a risk of a therapy failure.     

外周血循环肿瘤细胞在卵巢癌化疗中的临床应用

目的 探讨卵巢癌患者外周血中循环肿瘤细胞（CTC）变化情况与化疗疗效的关系。方法 选择2013年2月至2015年4月间在我院接受化疗的卵巢癌患者28例,分别抽取其化疗前后外周静脉血4 ml,采用免疫磁珠微粒阴性富集技术和免疫荧光原位杂交技术（imFISH）检测CTC数目,以CTC≥2个/3.2 ml定义为阳性。采用RECIST 1.0版标准评价化疗疗效,观察化疗前后CTC变化与疗效的关系。结果 化疗前外周血CTC阳性率为60.71％（17／28）,其与肿瘤分期（P=0.019）及CA125水平（P=0.022）有关;化疗后CTC阳性率为25％（7／28）。根据化疗前后CTC的变化,将患者分为阳性 阳性、阳性 阴性、 阴性 阳性、阴性 阴性4组,4组有效率分别为80.0％（4／5）、83.3％（10／12）、0（0／2）和88. 9％（8／9）,差异有统计学意义（P=0.045）。结论 化疗前后CTC变化与疗效有一定关系,CTC可作为评估卵巢癌化疗疗效的参考指标。     

乳腺癌新辅助化疗中循环肿瘤细胞的动态变化及疗效观察

  目的  通过检测新辅助化疗乳腺癌患者化疗前及化疗后各周期外周血中循环肿瘤细胞的变化,比较TC及TEC两种不同新辅助化疗方案的疗效。  方法  选取2010年1月~2012年12月间本院收治的96例局部晚期乳腺癌患者,随机分为两组,分别给予TC（多西他赛+环磷酰胺）和TEC（多西他赛+表柔比星+环磷酰胺）两种方案4个周期。分别抽取新辅助化疗前、新辅助化疗1、2、3、4个疗程后48h患者外周血5 mL,并采用流式细胞术测量外周血中循环肿瘤细胞含量,比较两种新辅助化疗方案疗效。  结果  两组患者新辅助化疗前年龄、绝经状态、ER、PR、C-erbB-2、肿物大小、临床分期等一般资料无统计学差异;两组患者新辅助化疗前外周血中循环肿瘤细胞值无明显差异;新辅助化疗前,两组患者外周血中循环肿瘤细胞含量与肿物体积有关系,肿物>5 cm者循环肿瘤细胞含量明显高于肿物≤5 cm者（P均 < 0.05）;两种新辅助化疗方案化疗后,两组患者外周血中循环肿瘤细胞值随化疗周期进行而持续降低（P均 < 0.05）,同时,使用TEC方案患者外周血中循环肿瘤细胞值明显低于使用TC方案患者（P均 < 0.05）。  结论  使用TC和TEC方案新辅助化疗可使局部晚期乳腺癌患者病灶缩小,外周血中循环肿瘤细胞值降低。同时,监测外周血中循环肿瘤细胞值变化,可评价新辅助化疗方案疗效。      

晚期卵巢癌患者外周血循环肿瘤细胞的检测及其临床意义

目的:探讨晚期卵巢癌患者外周血中循环肿瘤细胞(CTC)的检测及其临床意义.方法:选择2014年6月至2016年6月永州市中心医院收治的60例晚期卵巢癌患者作为观察组,收集同期本院的30例健康志愿者作为对照组.分别抽取外周血7.5 ml,采用流式细胞仪检测卵巢癌患者一线方案化疗2周期前后及对照组外周血中EpCAM、CK19同时(+)且CD45(-)的CTC的变化情况,同时分析其与临床特征及化学疗效的关系以及比较化疗前后CTC数目评价与RECIST疗效评价标准之间的关系,并随访患者的无进展生存期(PFS),分析患者治疗过程中CTC数目的变化与患者PFS的关系.结果:观察组中42例检测到CTC,阳性率70%,对照组未检测到CTC,两组比较,差异具有统计学意义(P<0.05).CTC阳性表达情况与卵巢癌患者的分化程度及CA125表达相关(P<0.05),与患者的年龄、肿瘤直径、腹水情况均无相关性(P>0.05).观察组中化疗前CTC阳性表达42例,阳性率为70%,化疗2周期后卵巢癌患者CTC阳性表达18例,阳性率为30%,两组差异具有统计学意义(P<0.05).化疗2周期后,CTC数目评价与RECIST疗效评价标准之间差异无统计学意义(P>0.05),且两种方法的吻合度较高(k=0.479).运用相关分析显示,CTC表达与化学疗效呈负相关(r=-0.223,P=0.009).化疗2周期后外周血中循环肿瘤细胞数目<5,其无进展生存期为13.2(11.0~15.1)个月,外周血中循环肿瘤细胞数目≥5,其无进展生存期为6.4(3.8~9.2)个月,两组差异具有统计学意义(P<0.05).结论:CTC阳性表达与卵巢癌患者的分化程度及CA125表达相关,与化疗疗效呈负相关,CTC的表达情况可以预测卵巢癌患者的化疗疗效及预后.     

Prognostic value of circulating tumor cells’ reduction in patients with extensive small-cell lung cancer

Objectives

Circulating tumor cells (CTCs) have been hypothesized to be a prognostic factor in small-cell lung cancer (SCLC), and different cutoffs have been proposed to identify patients at high risk. We assessed the prognostic value of CTCs in patients with extensive SCLC.

Materials and methods

CTCs were assessed with the CellSearch system in 60 extensive SCLC patients. CTC count at baseline or after one cycle of chemotherapy (cycle-1) or as change after chemotherapy were analyzed separately. Primary outcome was overall survival. The accuracy of prognostic role was assessed by Harrell's c-index. “Optimal” cutoffs were derived by bootstrap resampling to reduce the overfitting bias; accuracy improvement was estimated by calculating the difference of c-indexes of models including clinical variables with or without CTCs.

Results

CTCs were identified in 90% (54/60) of patients at baseline, in which CTC count ranged from 0 to 24,281. CTC count was strongly associated with the number of organs involved. The prognostic accuracy was only marginally increased by the addition to clinical information of “optimal” CTC cutoffs at baseline and after cycle-1. Conversely, a reduction of CTC count higher than 89% following chemotherapy significantly improved prognostic accuracy (bootstrap p-value = 0.009) and was associated with a lower risk of death (HR 0.24, 95% CI 0.09–0.61). When previously proposed cutoffs were applied to our cohort, they showed only marginal improvement of the prognostic accuracy.

Conclusion

CTCs have useful prognostic role in extensive SCLC, but only the change of CTC count after the first cycle of chemotherapy provides clinically relevant information. Previously reported CTC cutoffs were not prognostic in our cohort of patients.     

A nonrandomized,prospective, clinical study on the impact of circulating tumor cells on outcomes of urothelial carcinoma of the bladder patients treated with radical cystectomy with or without adjuvant chemotherapy

To investigate outcomes of urothelial carcinoma of the bladder (UCB) patients treated with radical cystectomy (RC) according to the presence of circulating tumor cells (CTC) and the administration of adjuvant chemotherapy (AC). We prospectively enrolled 226 UCB patients treated with RC without neoadjuvant chemotherapy at our institution between 2007 and 2013. Blood samples were obtained from all patients preoperatively and analyzed for CTC using the CellSearch^® system. Platinum‐based AC was administered in 50 patients (27.0%). Cox regression models evaluated the association of CTC with disease recurrence, cancer‐specific and overall mortality according to AC administration. 185 patients were available for analyses. CTC were present in 41 patients (22.2%). Patients with presence of CTC received AC more frequently, compared to patients without CTC (p = 0.027). At a median follow‐up of 31 months, the presence of CTC was associated with disease recurrence, cancer‐specific and overall mortality (p‐values < 0.001) in patients without AC administration. In patients who received AC, there was no difference in either endpoint between patients with or without presence of CTC. In multivariable analysis of patients without AC administration, the presence of CTC was an independent predictor for disease recurrence (HR: 4.9; p < 0.001), cancer‐specific (HR: 4.2; p = 0.003) and overall mortality (HR: 4.2; p = 0.001). The CTC status may be implemented in decision‐making regarding AC administration in UCB patients following RC. CTC measurement should be implemented in future UCB studies on systemic chemotherapy to validate our findings.     

The dynamic change of circulating tumour cells in patients with operable breast cancer before and after chemotherapy based on a multimarker QPCR platform

Background:

The possible presence of early tumour dissemination is the rationale behind the use of systemic adjuvant chemotherapy in patients with operable breast cancer. Circulating tumour cells (CTC) in peripheral blood may represent the possible presence of early tumour dissemination. However, relatively few studies were designed to investigate the relationship between the change of CTC status and the efficacy of adjuvant chemotherapy in operable breast cancer patients.

Methods:

In a prospective study, we established a multimarker real-time quantitative PCR platform to detect CTC in peripheral blood of breast cancer patients. By using this platform, we detected CTC in peripheral blood of 94 operable breast cancer patients. Control group consisted of 20 patients with benign breast disease and 20 healthy volunteers. For 72 patients who underwent systemic adjuvant chemotherapy, the dynamic CTC status at three different time points (1 day before initiation of chemotherapy, 1 week after three cycles of chemotherapy and 1 week after all cycles of chemotherapy) was observed.

Results:

Circulating tumour cells were detected in 56% (53 out of 94) of patients with operable breast cancer. The specificity was 95%. Seventy-two patients who received systemic adjuvant chemotherapy were followed up. After three cycles of chemotherapy, 47% (18 out of 38) of patients who were CTC-positive before chemotherapy changed into negative status. In addition, another 5% (2 out of 38) of patients had changed into negative status after all cycles of chemotherapy.

Conclusion:

Systemic adjuvant chemotherapy had a significant impact on CTC status, and this effect could be observed after three cycles of chemotherapy. Circulating tumour cells detection had the potential to be used to evaluate the efficacy of systemic adjuvant chemotherapy immediately after the chemotherapy was finished in operable breast cancer patients.     

Acute phase dynamics of circulating tumor cells after paclitaxel and doxorubicin chemotherapy in breast cancer mouse models

Purpose

Circulating tumor cells (CTCs) can provide a potentially minimal invasive source for monitoring chemotherapeutic effects. However, detailed in vivo dynamics of CTC after chemotherapy remain largely unknown.

Methods

We monitored CTC number and morphology early after chemotherapy using a newly developed cytology-based CTC detection device and triple-negative breast cancer mouse CTC models with spontaneous lung metastatic potential.

Results

Paclitaxel inhibited cell growth of breast cancer cells by mainly G2/M cell cycle arrest and partly apoptosis, whereas doxorubicin inhibited cell growth mainly by apoptosis and partly G2 cell cycle arrest in vitro. The number of CTCs was significantly increased 3–10 days after paclitaxel and doxorubicin chemotherapy and decreased thereafter in two mouse CTC models. The transiently increased CTCs early post-chemotherapy consisted of not only G2/M arrested cells (apoptotic cells), but also morphologically near-intact live cells. This heterogeneous cell population of CTCs was similar to that of primary tumor tissue after chemotherapy.

Conclusions

These results indicate that CTCs can be mobilized from the primary tumor in rapid response to chemotherapy and suggest the possibility that CTC monitoring from both numerical and morphological viewpoints early after chemotherapy using a cytology-based CTC detection device would be a useful diagnostic tool for predicting drug sensitivity/resistance in preclinical and clinical setting.

     

Circulating Tumor Cells Following First Chemotherapy Cycle: An Early and Strong Predictor of Outcome in Patients With Metastatic Breast Cancer

We investigated the prognostic significance of circulating tumor cells (CTCs) determined immediately before the second cycle of chemotherapy in patients with metastatic breast cancer (MBC). The CTC counts were taken at baseline, before the first cycle of chemotherapy (CTC‐0), and on day 21 before commencing the second cycle of chemotherapy (CTC‐21) in consecutive MBC patients. The study's primary objectives were to analyze relationships between CTC‐21 count and overall survival (OS). Based on the current literature, the CTC measurements were dichotomized as 0–4 versus ≥5 CTCs. Of 117 patients recruited, 99 were evaluable. Patients with 0–4 CTCs on day 21 had a significantly better OS than those with ≥5 CTCs (median OS: 38.5 months vs. 8.7 months). They also had a significantly better progression‐free survival (PFS; median: 9.4 months vs. 3.0 months) and clinical benefit rate (77% vs. 44%). The OS of patients whose baseline CTCs were ≥5 but dropped to <5 on day 21 was apparently similar to those who had <5 CTCs at baseline. In a Cox regression analysis, CTC‐21 was the only independent variable significantly predicting OS and PFS. Our data indicate that CTCs determined immediately before the second cycle of chemotherapy is an early and strong predictor of treatment outcome in MBC patients.     

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.