Circulating Tumor Cells Positive Rate Research Articles

Presence of molecular residual disease after pathologic complete response among patients with inflammatory breast cancer.

3044 Background: Inflammatory breast cancer (IBC) is known to recur more frequently than non-IBC after pathologic complete response (pCR). The presence of circulating tumor cells (CTCs), a marker of molecular residual disease (MRD), has been associated with higher likelihood of metastasis. We sought to characterize CTCs and its relationship with pCR in IBC patients. Methods: Patients diagnosed with IBC were enrolled in a prospective registry from 2005-2022. Serial blood draws were performed before, during, and after neoadjuvant systemic therapy (NST), and 6-months and 1-year post-surgery. CTCs were enumerated using CellSearch™. Patients with ≥ 1 CTC at any timepoint in the post-operative period were included in the positive CTC cohort. T-tests, one-way ANOVA, and chi-squared tests were used to compare differences between groups. Kaplan-Meier analysis was used for survival outcomes. Results: A total of 112 patients were included. The median age of diagnosis was 50.5 years (IQR 17) and BMI was 29.3 kg/m2 (IQR 11.3). Patients were predominantly White (85, 75.9%) with clinical stage IIIB-C (94, 84.9%), node-positive (107, 95.5%), and HER2-negative (66, 59.0%) disease. Almost all patients (109, 97.3%) received trimodality therapy – NST, modified radical mastectomy, and adjuvant radiation. At a median follow-up period of 7.1 years (95% CI: 4.7-9.4), the overall survival (OS) rate was 72.3%. Baseline CTC positivity rate was 61.8% (42/68). More than half of the patients (61, 54.5%) had a positive CTC at some point in the post-operative surveillance period. Among the 39 patients who achieved pCR (34.8%), 15 (38.5%) had positive CTCs during follow-up. There were no differences in age, BMI, menopause status, clinical stage, nodal status, grade, presence of LVI, and number of lymph nodes (LNs) removed by CTC status. However, patients with positive CTCs had a significantly higher number of positive LNs at resection (p = 0.01), were more likely to be HER2-negative (p = 0.001), and were less likely to achieve pCR (p = 0.01). Triple negative disease (p < 0.0001), lack of pCR (p = 0.006), and positive CTCs (0.007) were associated with poor prognosis. When pCR was combined with CTC status, patients with positive CTCs demonstrated significantly worse survival, despite having achieved pCR, compared to those with pCR and negative CTC status (5-year OS: 35.0% vs. 83.1%, respectively, p = 0.016). Conclusions: A high proportion of IBC patients who achieved pCR had MRD, as demonstrated by persistent CTCs. CTCs portended worse prognosis in patients with IBC, even after pCR. Future incorporation of longitudinal CTC monitoring may be helpful in identifying patients at risk for relapse despite having achieved a pCR. [Table: see text]

Peripheral arterial rather than venous blood is a better source of circulating tumor cells in early lung cancer.

Circulating tumor cells (CTCs) play a crucial role in the early diagnosis and prognosis of lung cancer. Identification of a more suitable sample source could be a breakthrough towards enhancing CTC detectability in early-stage lung cancer. We investigated the differences in detectable CTCs between peripheral arterial and venous blood in early- and mid-stage lung cancer patients undergoing surgery and analyzed the association between clinicopathological factors and detectable CTCs in peripheral arterial and venous blood. Peripheral arterial and venous blood was collected in 5-mL samples from 56 patients with surgically resected and pathologically clear at early- or mid-stage lung cancer. Blood specimens were enriched for CTCs based on isolation by size of epithelial tumor cells. The CTCs were identified using Swiss Giemsa staining and immunohistochemistry for CD45/CD31. In stage I lung cancer, CTC-positive rate was significantly higher in peripheral arterial than in venous blood (45.45% vs. 17.39%). There was no significant difference in the number of detectable CTCs between peripheral arterial and venous blood. A low degree of differentiation was associated with a high positive rate of CTCs in peripheral venous blood. The number of circulating tumor microemboli was significantly higher in patients with tumor size >3 cm compared with ≤3 cm. CTC levels in peripheral arterial and venous blood differed little in lung cancer patients.Compared to peripheral venous blood, peripheral arterial blood had a higher CTC positivity rate in early-stage lung cancer.This study was favorable for early detection and monitoring of lung cancer.

Circulating tumor cells (CTCs) and hTERT gene expression in CTCs for radiotherapy effect with lung cancer

BackgroundCirculating tumor cells (CTCs) are important biological indicators of the lung cancer prognosis, and CTC counting and typing may provide helpful biological information for the diagnosis and treatment of lung cancer.MethodsThe CTC count in blood before and after radiotherapy was detected by the CanPatrol™ CTC analysis system, and the CTC subtypes and the expression of hTERT before and after radiotherapy were detected by multiple in situ hybridization. The CTC count was calculated as the number of cells per 5 mL of blood.ResultsThe CTC positivity rate in patients with tumors before radiotherapy was 98.44%. Epithelial–mesenchymal CTCs (EMCTCs) were more common in patients with lung adenocarcinoma and squamous carcinoma than in patients with small cell lung cancer (P = 0.027). The total CTCs (TCTCs), EMCTCs, and mesenchymal CTCs (MCTCs) counts were significantly higher in patients with TNM stage III and IV tumors (P < 0.001, P = 0.005, and P < 0.001, respectively). The TCTCs and MCTCs counts were significantly higher in patients with an ECOG score of > 1 (P = 0.022 and P = 0.024, respectively). The TCTCs and EMCTCs counts before and after radiotherapy affected the overall response rate (ORR) (P < 0.05). TCTCs and ECTCs with positive hTERT expression were associated with the ORR of radiotherapy (P = 0.002 and P = 0.038, respectively), as were TCTCs with high hTERT expression (P = 0.012). ECOG score (P = 0.006) and post-radiation TCTCs count (P = 0.011) were independent factors for progression-free survival (PFS) and TNM stage (P = 0.054) and pre-radiation EMCTCs count (P = 0.009) were independent factors of overall survival (OS).ConclusionThis study showed a high rate of positive CTC detection in patients with lung cancer, and the number, subtype, and hTERT-positive expression of CTCs were closely related to patients’ ORR, PFS, and OS with radiotherapy. EMCTCs, hTERT-positive expression of CTCs are expected to be important biological indicators for predicting radiotherapy efficacy and the prognosis in patients with lung cancer. These results may be useful in improving disease stratification for future clinical trials and may help in clinical decision-making.

A NOVEL NOMOGRAM TO PREDICT RESECTABLE GASTRIC CANCER BASED ON PREOPERATIVE CIRCULATING TUMOR CELL (CTC).

BACKGROUND Circulating tumor cells (CTCs) have been suggested to have an important prognostic role in gastrointestinal tumors. We developed a preoperative CTC-based nomogram to predict the prognosis of patients with resectable gastric cancer after surgery and established a risk stratification system based on the nomogram. METHODS From January 2012 to June 2017, we screened 258 gastric cancer patients treated with surgery from 1 center as the training cohort and 133 gastric cancer patients treated with surgery from another as the validation cohort, screened prognostic factors for the training cohort using univariate and multivariate COX risk proportional models, created predictive overall survival (OS) and recurrence-free survival (RFS) nomogram, and plotted the receiver operating curve (ROC) as well as the calibration curve for this nomogram in the training and validation cohorts. Risk score stratification was performed according to the nomogram, and overall survival (OS) survival curves were plotted for the low, medium, and high-risk groups using the Kaplan-Meier method. RESULTS The CTC positivity rate was 78.5% in all patients. CTC, TNM stage, and Ki-67 were the prognostic factors affecting OS and RFS after gastric cancer surgery. Nomogram consisted of these 3 variables. in the training group, the area under the curve (AUC) of nomogram at 1, 3, and 5 years OS were 0.918,0.829 and 0.813, respectively, and the area under the curve (AUC) for RFS was 0.900, 0884 and 0.839, respectively. There was a statistically significant difference in OS among the low, medium, and high-risk groups according to the risk stratification system constructed from nomogram scores (P<0.001). CONCLUSIONS Two nomograms based on preoperative CTC were established to predict overall and recurrence-free survival after resectable gastric cancer. The 2 nomograms had good discrimination and calibration and significant stratification ability of the risk stratification system established according to them.

Correlation between circulating tumor cells and different molecular biological characteristics in breast cancer patients.

This study sought to detect the number of circulating tumor cells (CTCs) in breast cancer patients, and examine the relationship between CTCs and molecular biological characteristics. From June 2016 to June 2018, 150 female patients with invasive breast cancer detected by CTCs at the Department of Breast Surgery, Fudan University Cancer Hospital were enrolled in this study. The patients had an average age of 52.6±7.8 (range, 35-77) years. Routine pathological and immunohistochemical examinations were performed on tissues obtained during surgery. In this study, CTCs were detected using the immunomagnetic bead negative enrichment technique (i.e., the Cyttel technique). The measurement data are expressed by x ± s, and were compared by t-tests. A univariate analysis of variance was used to compare differences between groups. The count data are expressed as the absolute value, and the test χ2 or Fisher's exact test were used to compare differences. There were 109 cases of positive CTC (≥3 CTCs/4 mL) (72.7%), and 41 cases of negative CTC (<3 CTCs/4 mL) (27.3%). There were no significant differences in terms of age and menopausal status between the two groups (P>0.05). There was no significant difference in the positive rate of CTC in T1, T2, and T3 and above patients (P>0.05). There was no significant difference in the CTC positive rate between ER positive and negative patients, PR positive and negative patients, and Ki-67 ≥14% and <14% patients (P>0.05). However, there was a statistical difference in the positive rate of CTC between human epidermal growth factor receptor 2 (HER-2) positive and negative patients (P<0.05). There was no significant difference in the CTC positive rate among patients with Luminal A type, B type, HER-2 overexpression type, and triple negative breast cancer (TNBC) (P>0.05). There was no significant difference in the positive rate of CTC among patients with invasive ductal carcinoma, invasive lobular carcinoma, and other types of invasive carcinoma (P>0.05). It can be concluded that there is a relationship between CTC and HER-2 expression, which has certain predictive value for patients with positive HER-2 expression, thus predicting poor prognosis.

Circulating tumor cells detected with a microcavity array predict clinical outcome in hepatocellular carcinoma.

The present study aimed to establish a novel isolation strategy for circulating tumor cells (CTCs) using a microcavity array (MCA) system and to evaluate the clinical significance of CTCs in hepatocellular carcinoma (HCC). We examined recovery rates of HCC cell lines spiked into whole blood in MCA assay. Circulating tumor cells were isolated from peripheral blood samples (3 mL) of 7 healthy donors (HD), 14 patients with liver cirrhosis (LC), and 31 patients with HCC using the MCA system. Additionally, we investigated the mRNA expression of liver‐specific genes in isolated CTCs using qPCR. The recovery rates were 65.1% (HepG2), 76.7% (HuH7), and 99.0% (PLC/PRF/5). In HD and patients with LC and HCC, the CTC positivity rate (CTCs ≥10) and average CTC number were as follows: HD 0% and 0.1, LC 14.3% and 5.3, HCC 54.8% and 47.6, respectively. The CTC positivity rate in HCC was significantly higher than that in LC (p < 0.05). The number of CTCs was significantly higher in metastatic HCC (102.2 ± 160.6) than in localized HCC (8.2 ± 7.7) (p < 0.05). The expression of AFP, glypican‐3, EpCAM, and albumin (ALB) genes was detected in isolated CTCs. The positive CTCs (CTCs ≥10) significantly reduced the cumulative survival in patients with HCC (p = 0.025), especially in localized patients with HCC (p = 0.046). The newly developed MCA system has the potential to isolate CTCs from HCC with high sensitivity, and mRNA expression could be measured from CTCs. Identification of positive CTCs can help predict clinical outcome of patients with HCC. Thus, analysis of CTCs in patients with HCC may provide important information as a novel biomarker in disease progression.

Co-Expression of Stem Cell and Epithelial Mesenchymal Transition Markers in Circulating Tumor Cells of Bladder Cancer Patients.

ObjectiveCancer cells with stemness and epithelial-to-mesenchymal transition (EMT) features display enhanced malignant and metastatic potential. This study aimed to introduce a new methodology developed in order to investigate the co-expression of a stemness (OCT4) and EMT markers on single circulating tumor cells (CTCs) of patients with localized urinary bladder cancer and their potential prognostic prediction value.Methods and MaterialsBetween April 2015 and July 2015, blood samples of 51 consecutive patients diagnosed with high risk bladder cancer (cT1-3N0M0) were prospectively investigated for CTCs. Peripheral blood (5 mL) was drawn before primary transurethral resection. Detection of CTCs was performed using the CanPatrolTM system. Nucleic acid probes were used to identify CTCs, and expression levels of epithelial and mesenchymal genes in CTCs were examined by situ hybridization assay.ResultsAll patients received radical cystectomy with pelvic lymph nodes dissection. CTCs were detected in 44 of 51 (86.3%) patients, respectively. The overall mean number of CTCs was 6.1 (range: 0~29; median: 4). A total of 311 CTCs were detected in PB. High OCT4 expression (OCT4high) was detected more frequently in Epi−Mes+ cells (p=0.001). Patients with pathological confirmed muscle-invasive bladder cancer (MIBC) had higher Epi−Mes+ CTCs positive rates (p=0.001) and OCT4high CTCs positive rates (p=0.019) than pathological confirmed non muscle-invasive bladder cancer (NMIBC). Regarding co-expression of these markers, Epi−Mes+/OCT4high CTCs were more frequently evident in the MIBC setting (30.4% vs 3.6% of patients, p = 0.016).ConclusionA differential expression pattern for these markers was observed both in NMIBC and MIBC disease. A subgroup of CTCs showed a CTCs expressing high OCT4, along with Mes were more frequently detected in patients with MIBC, suggesting that these cells may prevail during tumor muscle invasion and disease progression.

Clinical relevance of circulating tumor cells in ovarian, fallopian tube and peritoneal cancer

PurposePresence of circulating tumor cells (CTCs) is associated with impaired clinical outcome in several solid cancers. Limited data are available on the significance of CTCs in gynaecological malignancies. The aims of the present study were to evaluate the dynamics of CTCs in patients with ovarian, fallopian tube and peritoneal cancer during chemotherapy and to assess their clinical relevance.Methods43 patients with ovarian, fallopian tube and peritoneal cancer were included into this prospective study. Patients received chemotherapy according to national guidelines. CTC analysis was performed using the CellSearch system prior to chemotherapy, after three and six cycles.ResultsIn 26% of the patients, ≥ 1CTC per 7.5 ml of blood was detected at baseline (17% of patients with de novo disease, compared to 35% in recurrent patients). Presence of CTCs did not correlate with other factors. After three cycles of therapy, CTC positivity rate declined to 4.8%. After six cycles, no patient showed persistent CTCs. Patients with ≥ 1 CTC at baseline had significantly shorter overall survival and progression-free survival compared to CTC-negative patients (OS: median 3.1 months vs. not reached, p = 0.006, PFS: median 3.1 vs. 23.1 months, p = 0.005). When only the subgroup with newly diagnosed cancer was considered, the association between CTC status and survival was not significant (OS: mean 17.4 vs. 29.0 months, p = 0.192, PFS: 14.3 vs. 26.9 months, p = 0.085). Presence of ≥ 1 CTC after three cycles predicted shorter OS in the entire patient cohort (p < 0.001).ConclusionsHematogenous tumor cell dissemination is a common phenomenon in ovarian, fallopian tube and peritoneal cancer. CTC status before start of systemic therapy correlates with clinical outcome. Chemotherapy leads to a rapid decline in CTC counts; further research is needed to evaluate the clinical value of CTC monitoring after therapy.

Less micrometastatic risk related to circulating tumor cells after endoscopic breast cancer surgery compared to open surgery

BackgroundIncrease of circulating tumor cells (CTCs) has been found after surgery for various carcinomas but not confirmed for breast cancer, and whether endoscopic surgery confers identical effect to CTCs as open surgery did is not clear. The present study aimed to investigate whether CTCs increase after surgery and whether there is a difference between open surgery and endoscopic surgery.MethodsPre- and postoperative peripheral blood (5 mL) obtained from 110 female patients with operable breast cancer (53 underwent endoscopic surgery, 57 underwent open radical mastectomy). Quantitative real-time reverse transcription-PCR was done to detect cytokeratin 19 mRNA-positive CTC. CTC detection rate, cell number and the increase after surgery (named micrometastasis) were compared between the two groups.ResultsIn the open group, CTC positive rate before and after surgery were 22.81 and 33.33%; median CTC number before and after surgery were 0.21 and 0.43 and 17 patients (29.82%) had increased micrometastatic risk. In the endoscopic group, CTC positive rate before and after surgery were 24.53 and 28.30%; median CTC number before and after surgery were 0.27 and 0.36, and 8 patients (15.09%) had increased micrometastatic risk. There was a suggestive higher postoperative CTC detection rate and CTC number and a significant increased postoperation micrometastatic risk was observed in the open group compared to the endoscopic group (OR = 3.19, 95%CI: 1.05–9.65) after adjustment for clinicopathologic characteristics.DiscussionCTC tends to increase in breast cancer patients after surgery, and the micrometastatic risk was higher for open surgery compared to endoscopic surgery.Trial registrationThis study was prospectively registered at Chinese Clinical Trial Register (ChiCTR-OCH-10000859, 24 April 2010).

A simple pyramid-shaped microchamber towards highly efficient isolation of circulating tumor cells from breast cancer patients.

Isolation and detection of circulating tumor cells (CTCs) has showed a great clinical impact for tumor diagnosis and treatment monitoring. Despite significant progresses of the existing technologies, feasible and cost-effective CTC isolation techniques are more desirable. In this study, a novel method was developed for highly efficient isolation of CTCs from breast cancer patients based on biophysical properties using a pyramid-shaped microchamber. Through optimization tests, the outlet height of 6μm and the flow rate of 200μL/min were chosen as the optimal conditions. The capture efficiencies of more than 85% were achieved for cancer cell lines (SKBR3, BGC823, PC3, and H1975) spiked in DMEM and healthy blood samples without clogging issue. In clinic assay, the platform identified CTCs in 13 of 20 breast cancer patients (65%) with an average of 4.25 ± 4.96 CTCs/2mL, whereas only one cell was recognized as CTC in 1 of 15 healthy blood samples. The statistical analyses results demonstrated that both CTC positive rate and CTC counts were positive correlated with TNM stage (p<0.001; p = 0.02, respectively). This microfluidic platform successfully demonstrated the clinical feasibility of CTC isolation and would hold great potential of clinical application in predicting and monitoring the prognosis of cancer patients.

Filtration based assessment of CTCs and CellSearch\xae based assessment are both powerful predictors of prognosis for metastatic breast cancer patients

BackgroundThe assessment of circulating tumor cells (CTCs) has been shown to enable monitoring of treatment response and early detection of metastatic breast cancer (MBC) recurrence. The aim of this study was to compare a well-established CTC detection method based on immunomagnetic isolation with a new, filtration-based platform.MethodsIn this prospective study, two 7.5 ml blood draws were obtained from 60 MBC patients and CTC enumeration was assessed using both the CellSearch® and the newly developed filtration-based platform. We analyzed the correlation of CTC-positivity between both methods and their ability to predict prognosis. Overall survival (OS) was calculated and Kaplan-Meier curves were estimated with thresholds of ≥1 and ≥5 detected CTCs.ResultsThe CTC positivity rate of the CellSearch® system was 56.7% and of the filtration-based platform 66.7%. There was a high correlation of CTC enumeration obtained with both methods. The OS for patients without detected CTCs, regardless of the method used, was significantly higher compared to patients with one or more CTCs (p < 0.001). The median OS of patients with no CTCs vs. ≥ 1 CTC assessed by CellSearch® was 1.83 years (95% CI: 1.63–2.02) vs. 0.74 years (95% CI: 0.51–1.52). If CTCs were detected by the filtration-based method the median OS times were 1.88 years (95% CI: 1.74–2.03) vs. 0.59 years (95% CI: 0.38–0.80).ConclusionsThe newly established EpCAM independently filtration-based system is a suitable method to determine CTC counts for MBC patients. Our study confirms CTCs as being strong predictors of prognosis in our population of MBC patients.

Analysis of Circulating Tumor Cells in Ovarian Cancer and Their Clinical Value as a Biomarker

Background/Aims: Monitoring the appearance and progression of tumors are important for improving the survival rate of patients with ovarian cancer. This study aims to examine circulating tumor cells (CTCs) in epithelial ovarian cancer (EOC) patients to evaluate their clinical significance in comparison to the existing biomarker CA125. Methods: Immuomagnetic bead screening, targeting epithelial antigens on ovarian cancer cells, combined with multiplex reverse transcriptase-polymerase chain reaction (Multiplex RT-PCR) was used to detect CTCs in 211 samples of peripheral blood (5 ml) from 109 EOC patients. CTCs and CA125 were measured in serial from 153 blood and 153 serum samples from 51 patients and correlations with treatment were analyzed. Immunohistochemistry was used to detect the expression of tumor-associated proteins in tumor tissues and compared with gene expression in CTCs from patients. Results: CTCs were detected in 90% (98/109) of newly diagnosed patients. In newly diagnosed patients, the number of CTCs was correlated with stage (p=0.034). Patients with stage IA-IB disease had a CTC positive rate of 93% (13/14), much higher than the CA125 positive rate of only 64% (9/14) for the same patients. The numbers of CTCs changed with treatment, and the expression of EpCAM (p=0.003) and HER2 (p=0.035) in CTCs was correlated with resistance to chemotherapy. Expression of EpCAM in CTCs before treatment was also correlated with overall survival (OS) (p=0.041). Conclusion: Detection of CTCs allows early diagnose and expression of EpCAM in CTC positive patients predicts prognosis and should be helpful for monitoring treatment.

Detection and clinical significance of circulating tumor cells in patients with gastrointestinal stromal tumors

Objective To explore the relationship between the circulating tumor cells (CTCs) and clinicopathologic factors in gastrointestinal stromal tumors (GIST) patients, and evaluate the role of CTCs in predicting prognosis of GIST patients. Methods The CTCs in peripheral blood of 86 cases of GIST were detected based on nanochip platform, and the captured CTCs identified by immunofluorescence staining. The cumulative survival and progression-free survival rate in GIST patients were assessed by Kaplan-Meier method. Results CTCs were detected in 44 GIST patients, and CTCs positive rate was 51.2%. The CTCs positive rate was correlated with tumor size, mitotic count, and risk level, but not with gender, tumor location, clinical staging, morphology, lymphatic metastasis, and Ki-67. The median survival time in the CTCs negative patients [(52.76±3.48) months] was significantly higher than that in the CTCs positive group [(45.39±2.78) months, P=0.007). The CTCs appeared as significantly independent prognostic factors with a relative risk of 2.362 [95% confidence interval (CI): 1.467-4.529, P=0.023] in Cox multivariate analysis. Conclusion Those results suggest that CTCs were implicated in tumor size, mitotic count, and risk level of GIST, and detection of CTCs facilitates a more accurate assessment of the disease. CTCs positive rate is closely related to the prognosis of GIST patients. Key words: Gastrointestinal stromal tumors; Circulating tumor cells; Clinical characteristics

Clinical value of circulating tumor cells detection in patients with colorectal cancer

Objective To investigate the association between the positive rate of circulating tumor cells (CTC) and clinicopathological parameters, recurrence and metastasis in patients with colorectal cancer. Methods 7.5 ml peripheral blood of 138 cases of newly diagnosed colorectal cancer who met inclusion criteria, 82 post-operative cases of colorectal cancer and 34 healthy controls were collected. The CTC was enriched by beads which packaged the anti epithelial cell adhesion molecule and counting the CTC (CK+ DAPI+ CD45-). To investigate the association between the preoperative positive rate of CTC and clinicopathological parameters, and the relationship between the positive rate of CTC and recurrence and metastasis in post-operative colorectal cancer patients who have not accepted any therapy more than one month. Results The positive rate of CTC in patients with colorectal cancer and healthy controls were 47.1% (65/138), and 0 (0/34) respectively, and the difference was statistically significant (χ 2= 25.743, P 0.05); The significant association between the positive rate of CTC and N or M staging was found. CTC positive rates in N0, N1, N2 stage were 38.3% (23/60), 37.9% (11/29), and 63.9% (23/36) respectively (χ 2= 6.819, P= 0.033); CTCs positive rates of M0, M1 stage were 38.0% (38/100) and 71.1% (27/38) respectively, and there was a statistical difference (χ 2= 12.074, P= 0.001). In 82 post-operative cases of colorectal cancer, the positive rates of CTC were 51.6% (32/62) and 90.0% (18/20) in non-recurrence and recurrence, respectively, and the difference was statistically significant (χ 2= 9.365, P= 0.002). Conclusion CTC detection may assess the occurrence of metastasis and recurrence in colorectal cancer patients. Key words: Colorectal neoplasms; Circulating tumor cells; Clinical value

MA08.07 Prospective Sequential Counts of Total CTC or cKIT+CTC in Advanced NSCLC with 1st Line Chemotherapy (POLICE)

Circulating tumor cells (CTCs) have been reported prognostic and predictive in non-small cell lung cancer (NSCLC) and a few of other cancer types. In 1st line setting, whether EPCAM+CK+CD45- CTC and/or stem cell-like cKIT+EPCAM+ CK+CD45- CTC enumeration and dynamic changes can be prognostic and/or predictive to standard chemotherapy need further investigation in Chinese patients with NSCLC. A prospective study on the CTC enumeration in advanced NSCLC with 1st line chemotherapy (POLICE) was started by China Thoracic Oncology Group (CTONG). Patients with NSCLC naïve for systemic regimens were enrolled since August 2013. CTCs were detected by Cell Search Platform and identified as positive for EPCAM+CK+CD45- phenotype. CD117 (cKIT) marker was added to test the frequency of stem cell-like cKIT+EPCAM+CK+CD45- CTCs. Primary endpoints were CTC counts and its correlation with first line therapy. Totally 180 patients were enrolled. In 174 case total CTC and cKIT+CTC positive (cutoff >=1) rates were 38.5% (67/172) vs 14.3% (24/168), 21.8% (31/142) vs 6.3% (9/142), 13.7% (13/95) vs 6.4% (6/94) and 40.4% (38/94) vs 15.0% (13/93) at time-points of baseline, after first-cycle-chemo, after four-cycles-chemo and disease progression. At time immediately after first-cycle-chemo, patients in CTC=0 group got statistically higher ORR (29.0% VS 7.1%, P=0.017) and DCR (74.2% VS 42.9%, P=0.002) than in CTC>=1 group. At time after four-cycles-chemo, patients in CTC=0 group got statistically higher DCR (88.3% VS 58.3%, P=0.026) than in CTC>=1 group. At time either after first-cycle-chemo or after four-cycles-chemo, patients in CTC>=1 group got worse PFS (5.7m VS 4.0m, P=0.025; 6.3m VS 4.0m, P=0.001 ) than in CTC=0 group. At time after first-cycle-chemo, patients in groups cKIT+CTC>=1 and cKIT-CTC>=1 got worse PFSs (3.1m vs 4.0m vs 5.7m, P=0.001) and worse DCRs (44.4% vs 42.1% vs 73.9%, P=0.009) than in CTC=0 group. For 142 patients categorized into three groups of dynamic CTC decrease (17), CTC unchanged (82), and CTC increase (43), there were significant differences in terms of DCR (71.8% vs 71.6% vs 33.3%, P=0.018) and PFS (5.2m vs 5.6m vs 3.1m, P=0.037). In first line setting of advanced NSCLC, at time-points after first-cycle-chemo other than baseline, total CTC or cKIT+CTC counts could be predictive for worse DCR or PFS. CTC increase from baseline to after-first-cycle-chemo might be a strong signal for the inefficacy of first line chemotherapy in the NSCLC patients.

Feasibility of a novel one-stop ISET device to capture CTCs and its clinical application.

IntroductionCirculating tumor cells (CTCs) play a crucial role in cancer metastasis. In this study, we introduced a novel isolation method by size of epithelial tumor cells (ISET) device with automatic isolation and staining procedure, named one-stop ISET (osISET) and validated its feasibility to capture CTCs from cancer patients. Moreover, we aim to investigate the correlation between clinicopathologic features and CTCs in colorectal cancer (CRC) in order to explore its clinical application.ResultsThe capture efficiency ranged from 80.3% to 88% with tumor cells spiked into medium while 67% to 78.3% with tumor cells spiked into healthy donors’ blood. In detection blood samples of 72 CRC patients, CTCs and clusters of circulating tumor cells (CTC-clusters) were detected with a positive rate of 52.8% (38/72) and 18.1% (13/72) respectively. Moreover, CTC positive rate was associated with factors of lymphatic or venous invasion, tumor depth, lymph node metastasis and TNM stage in CRC patients (p < 0.01). Lymphocyte count and neutrophil to lymphocyte ratio (NLR) were significantly different between CTC positive and negative groups (p < 0.01).Materials and MethodsThe capture efficiency of the device was tested by spiking cancer cells (MCF-7, A549, SW480, Hela) into medium or blood samples of healthy donors. Blood samples of 72 CRC patients were detected by osISET device. The clinicopathologic characteristics of 72 CRC patients were collected and the association with CTC positive rate or CTC count were analyzed.ConclusionsOur osISET device was feasible to capture and identify CTCs and CTC-clusters from cancer patients. In addition, our device holds a potential for application in cancer management.

Detection of circulating tumor cells in patients with breast cancer using the quantitative RT-PCR assay for monitoring of therapy efficacy

Circulating tumor cells (CTCs) are an independent prognostic factor for patients with breast cancer. However, the role of CTCs in early breast cancer management is not yet clearly defined. The aim of this study was to isolate and characterize CTCs in blood sample of a breast cancer patient as a biomarker for monitoring treatments efficacy. In this study, 692 blood samples from 221 breast cancer patients and 376 healthy individuals was used to detect CTCs with multiple markers including epithelial cell adhesion molecule (EpCAM), cytokeratin (CK) 19, human epidermal growth factor (HER) 2, Ki67, human telomerase reverse transcriptase (hTERT), and vimentin using quantitative reverse transcription PCR (RT-qPCR). A total of 153 (69.2%) blood samples of 221 patients with breast cancer were found to be positive for at least one of the cancer-associated marker gene before treatment. After chemotherapy, no CTCs were found in 28 (33.3%) of the 84 blood samples analyzed for the presence of CTCs using the RT-qPCR, whereas 56 (66.7%) blood samples were still found to be positive for at least one of the markers. After completing the therapy, the CTC positivity rate decreased to 7 (20.6%) in the neoadjuvant group, whereas this increased to 7 (14%) cases in the adjuvant group. There was no statistically significant relationship between TNM stage and detection of CTC-related markers. Data from this study suggest that RT-qPCR assay for the detection of CTC markers might be useful in selecting appropriate therapeutics and for monitoring treatment efficacy in breast cancer patients.

4EVER: Assessment of circulating tumor cells with a novel, filtration-based method, in a phase IIIb multicenter study for postmenopausal, HER2- negative, estrogen receptor-positive, advanced breast cancer patients.

591 Background: The presence of circulating tumor cells (CTCs) has been shown to be of prognostic relevance for patients with early and advanced breast cancer (BC). The usefulness of CTC assessments depends on accurate cell counts and corresponding analysis of molecular targets. The aim of this sub study was to assess the feasibility of a novel, integrated CTC platform for automated cellular protein and nucleic acid analysis in a prospective multi-center study. Methods: The German 4EVER study included patients with postmenopausal, metastastic, ER positive, HER2 negative BC, who progressed after therapy with a non-steroidal aromatase inhibitor and were treated with exemestane and the mTOR inhibitor everolimus. Baseline blood samples (TransFix vaccum tubes, Cytomark, Caltag Medsystems Ltd.) were used for CTC analysis and processed on the modified Versant kPCR Sample Prep system using 8µm pore size Whatman Nuclepore track-etched membranes (GE Healthcare Piscataway, NJ). After CTC capture, immunostaining was performed for Cytokeratin 8/18/19 and CD45. CTCs were detected by image analytics after fluorescence scanning microscopy using a dedicated software solution implemented by Siemens. The data is summarized and correlated with baseline clinical characteristics. Results: CTC counts and clinical data were available for 111 blood samples (91.7%). CTCs were found in 75 patients (67,6%), 13 patients having 1 CTC, 38 having 2-9 CTCs and 24 patients having 10 or more CTCs. In an exploratory analysis the presence of CTCs was correlated with baseline patient and tumor characteristics. There were no associations with primary TNM stage, hormone receptor status or tumor type. Conclusions: CTC assessment with this novel filtration based method was feasible in a multi-center study setting. The CTC positivity rate was within the expected range. The follow-up of this study will give first insights, how the CTC measures of this platform can be used as a prognostic tool. As this CTC assessment platform was developed to perform additional automated cellular protein and nucleic acid analysis, the usefulness might derive from these analytic tools as well. Clinical trial information: NCT01626222.

Meta-analysis of Circulating Tumor Cells as a Prognostic Marker in Lung Cancer

Recent studies have shown that circulating tumor cells (CTCs) play potential roles as diagnostic and prognostic biomarkers with various cancer types. The aim of this study was to comprehensively and quantitatively summarize the evidence for the use of CTCs to predict the survival outcome of lung cancer patients. Relevant literature was identified using Medline and EMBASE. Patients' clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CTC positive rates at different time points (before, during and after treatment) were extracted. A meta-analysis was performed to clarify the prognostic role of CTCs and the correlation between the CTC appearance and clinical characteristics. A total of 12 articles containing survival outcomes and clinical characteristics and 15 articles containing only clinical characteristics were included for the global meta-analysis. The hazard ratio (HR) for OS predicted by pro-treatment CTCs was 2.61 [1.82, 3.74], while the HR for PFS was 2.37 [1.41, 3.99]. The HR for OS predicted by post-treatment CTCs was 4.19 [2.92, 6.00], while the HR for PFS was 4.97 [3.05, 8.11]. Subgroup analyses were conducted according to histological classification and detection method. Odds ratio (OR) showed the appearance of pro-treatment CTCs correlated with the lymph node status, distant metastasis, and TNM staging, while post-treatment CTCs correlated with TNM staging only. Detection of CTCs in the peripheral blood indicates a poor prognosis in patients with lung cancer.

Association between the spread of circulating tumor cells and breast cancer subtypes

We read with great interest the recent publication by Fehm and coworkers [1] about the association between the spread of circulating tumor cells (CTCs) and breast cancer subtypes. Th e authors observed that the highest CTC positivity rate was obtained in triple-negative patients followed by those with estrogen receptor (ER)positive and/or progesterone receptor (PR)-positive tumors, while no CTCs could be detected in the human epidermal growth factor receptor 2 (HER2)-positive subtype group. However, another study [2] showed contradictory results, indicating that HER2 was the only primary tumor characteristic that correlated with the presence of CTCs, while ER and PR status were not association with their presence. To clarify the correlation between CTCs and breast cancer subtypes, a total of 156 operable breast cancer patients admitted to our hospital were enrolled. Th is study was approved by the regional ethics committee. Written informed consent was obtained from all participating patients. Mononuclear cell enrichment and CTC detection were done as previously described [3]. Th e expression of ER, PR and HER2 in primary tumors was routinely detected. Results showed that the overall positive rate of CTCs in operable breast cancer patients was 32.1% (50 out of 156). Th ere existed signifi cant diff erences in the positive rate of CTCs between patients at diff erent pTNM stages (P = 0.0219) and between those with diff erent immunohisto chemical subtypes (P = 0.0003). Further analysis revealed that the positive rate of CTCs in the HER2positive and triple-negative subtypes was signifi cantly higher than that of the luminal subtype ( P= 0.0034 and 0.0003, respectively). In subgroup analysis by pTNM stage, signifi cant diff erences in the positive rate of CTCs between patients with diff erent breast cancer subtypes were identifi ed at stages I (P = 0.0207), II (P = 0.0478) and III (P = 0.0324) (Table 1), further supporting that the presence of CTCs was associated with the HER2-positive and triple-negative subtypes.