Physical activity and/or dietary intervention in overweight or obese breast cancer survivors: results of the InForma randomized trial.

PURPOSE: This study aimed to test the efficacy of a 6-month intervention on weight loss in a group of overweight or obese breast cancer (BC) survivors. We promoted adherence to a healthy diet or/and to increase physical activity, making use of a step counter device. Here we present results regarding the change in anthropometric measures and blood parameters. METHODS: 266 women treated for BC with a BMI ≥ 25 kg/m2 were randomized to a 6-month intervention into four arms: Dietary Intervention (DI); Physical Activity Intervention (PAI); Physical Activity and Dietary Intervention (PADI); Minimal Intervention (MI). Women were offered individualized counseling by a dietitian, a physiotherapist and a psychologist. Participants were followed up for an additional 18 months. RESULTS: 231 women completed the 6-month intervention and 167 completed the additional 18-month follow-up. Respectively, 37.5% and 36.7% of women included in the DI and PADI arm reached the objective of the trial (weight reduction > 5%). Significant weight and circumferences decrease was observed at 6-month in the four arms. Weight decrease was more pronounced in the DI (-4.7% ± 5.0%) and PADI (-3.9% ± 4.5%) arms, persisted over time (at 12 and 24 months), where counseling was mainly focused on the dietic component. The intervention had an effect on the glucose level with a significant reduction in whole population (-0.9 ± 11.7 p-value 0.02) and most pronounced in the PADI arm (-2.4 ± 7.8 p-value 0.03). CONCLUSIONS: Lifestyle intervention mainly focused on the dietetic component and making use of a step counter improved body weight, circumferences and glucose levels. IMPLICATIONS FOR CANCER SURVIVORS: A personalized approach yields a potential clinical benefit for BC survivors.

Diagnostic Performance and Cell Count of EBUS-TBNA Needle Gauges: A Prospective Trial.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a well-established diagnostic procedure for evaluating hilar and mediastinal lymphadenopathies and is the gold standard for lung cancer diagnosis and staging. Recent studies assessed the effectiveness of the 19-G flex needle in obtaining larger EBUS-TBNA samples, and prospective small series gave similar results in terms of diagnostic yield when testing different gauge needles. The lack of homogeneity between series and the small sample size of some prospective cohorts poses a limit to the validity of those results. This prospective controlled study compared the 19-G flex and 22-G needles in terms of diagnostic yield. An objective laboratory method was used to count cells and compare the two needles' cytologic yields. MATERIAL: A prospective controlled study was conducted on 90 patients undergoing EBUS-TBNA for the diagnosis of hilar and mediastinal lymphadenopathies. The institutional ethic committee (IEO573) approved the study, and informed consent was obtained from all patients. RESULTS: A total of 90 patients were enrolled in this study, 84.4% of whom were diagnosed with malignancy and 15.6% with non-neoplastic disease. Sensitivity for malignancy was 93.4% (CI: 87.4-97.1%) for the 19-G needle and 92.6% (CI: 86.3-96.5%) for the 22-G needle (p = 0.80). The percentage of malignant cells in the cell block was 63.9% and 61.5% for the 22-G and 19-G needles, respectively. The cell count assessed by flow cytometry was 2071 cells/µL (IQR: 600,2265) with the 22-G needle and 2761 cells/µL (IQR: 505,3250) with the 19-G needle (p = 0.79). The malignant cell count was 0.05 × 103 cells/µL with the 22-G and 0.08 × 103 cells/µL with the 19-G needle (p = 0.70). There was no difference in the presence of tissue cores in the samples, and rapid on-site evaluation (ROSE) cellularity was comparable between the two needles. CONCLUSIONS: The 19-G flex EBUS-TBNA needle is comparable to the 22-G needle in terms of diagnostic yield for cyto-histological evaluation of hilar and mediastinal lymphadenopathies. There is no difference between the 19-G and 22-G needle cell counts evaluated by flow cytometry.

Intraoperative Extra Corporeal Membrane Oxygenator for Lung Cancer Resections Does Not Impact Circulating Tumor Cells.

BACKGROUND: The diagnosis of active neoplastic disease was traditionally judged an absolute contraindication for extracorporeal membrane oxygenator (ECMO) because of the fear of tumor cells being scattered or seeded. The aim of this study is to compare the number of circulating tumor cells (CTCs) before and after surgery in patients receiving lung cancer resection with and without intraoperative ECMO support. METHODS: This is a prospective, non-randomized, two-arms observational study comparing the number of CTCs before and after surgery in patients receiving lung cancer resection with and without intraoperative ECMO support. The ECMO arm includes patients suffering from lung cancer undergoing pulmonary resection with planned intraoperative ECMO support. The non-ECMO arm includes patients suffering from non-early-stage lung cancer undergoing pulmonary resection without planned intraoperative ECMO support. RESULTS: Twenty patients entered the study, eight in the ECMO arm and twelve in the non-ECMO arm. We did not observe any significant difference between the ECMO and non-ECMO groups in terms of postoperative complications (p = 1.00), ICU stay (p = 0.30), hospital stay (p = 0.23), circulating tumor cells' increase or decrease after surgery (p = 0.24), and postoperative C-reactive protein and C-reactive protein increase (p = 0.80). The procedures in the non-ECMO arm were significantly longer than those in the ECMO arm (p = 0.043). CONCLUSIONS: Intraoperative ECMO for lung cancer resections did not impact CTC increase or decrease after the procedure.

Addressing the Role of Angiogenesis in Patients with Advanced Pancreatic Neuroendocrine Tumors Treated with Everolimus: A Biological Prospective Analysis of Soluble Biomarkers and Clinical Outcomes.

BACKGROUND: The success of targeted therapies in the treatment of pancreatic neuroendocrine tumors has emphasized the strategy of targeting angiogenesis and the PI3K/AKT/mTOR pathway. However, the major challenge in the targeted era remains the early identification of resistant tumors especially when the efficacy is rarely associated to a clear tumor shrinkage at by imaging assessment. METHODS: In this prospective study (NCT02305810) we investigated the predictive and prognostic role of soluble biomarkers of angiogenesis turnover (VEGF, bFGF, VEGFR2, TSP-1) circulating endothelial cells and progenitors, in 43 patients with metastatic panNET receiving everolimus. RESULTS: Among all tested biomarkers, we found a specific subpopulation of circulating cells, CD31+CD140b-, with a significantly increased tumor progression hazard for values less or equal to the first quartile. CONCLUSION: Our study suggested the evidence that circulating cells might be surrogate biomarkers of angiogenesis activity in patients treated with everolimus and their baseline levels can be correlated with survival. However, further studies are now needed to validate the role of these cells as surrogate markers for the selection of patients to be candidates for antiangiogenic treatments.

The clinical use of circulating tumor cells (CTCs) enumeration for staging of metastatic breast cancer (MBC): International expert consensus paper.

BACKGROUND: The heterogeneity of metastatic breast cancer (MBC) necessitates novel biomarkers allowing stratification of patients for treatment selection and drug development. We propose to use the prognostic utility of circulating tumor cells (CTCs) for stratification of patients with stage IV disease. METHODS: In a retrospective, pooled analysis of individual patient data from 18 cohorts, including 2436 MBC patients, a CTC threshold of 5 cells per 7.5 ml was used for stratification based on molecular subtypes, disease location, and prior treatments. Patients with ≥ 5 CTCs were classified as Stage IVaggressive, those with < 5 CTCs as Stage IVindolent. Survival was analyzed using Kaplan-Meier curves and the log rank test. RESULTS: For all patients, Stage IVindolent patients had longer median overall survival than those with Stage IVaggressive (36.3 months vs. 16.0 months, P < 0.0001) and similarly for de novo MBC patients (41.4 months Stage IVindolent vs. 18.7 months Stage IVaggressive, p < 0.0001). Moreover, patients with Stage IVindolent disease had significantly longer overall survival across all disease subtypes compared to the aggressive cohort: hormone receptor-positive (44 months vs. 17.3 months, P < 0.0001), HER2-positive (36.7 months vs. 20.4 months, P < 0.0001), and triple negative (23.8 months vs. 9.0 months, P < 0.0001). Similar results were obtained regardless of prior treatment or disease location. CONCLUSIONS: We confirm the identification of two subgroups of MBC, Stage IVindolent and Stage IVaggressive, independent of clinical and molecular variables. Thus, CTC count should be considered an important tool for staging of advanced disease and for disease stratification in prospective clinical trials.

Serum HER2 extracellular domain levels and HER2 circulating tumor cell status in patients with metastatic breast cancer.

AIM: To shed light on the clinical role of HER2 status in serum as extracellular domain (ECD) and corresponding circulating tumor cells (CTCs) in metastatic breast cancer patients. METHODS: 68 patients were analyzed. Serum HER2 was determined by ADVIA Centaur(®) Serum HER2 test. CellSearch System was performed for CTC quantification. RESULTS: HER2 was overexpressed in 21 primary tumors. In total, 19 patients had ECD >15 ng/ml (the cut-off used), 48 patients had at least one CTC. ECD positivity was associated with CTC number (p = 0.01), HER2-positive CTC (p = 0.01) and the ratio HER2-positive CTC/total CTC (p = 0.02). ECD was not associated with survival. CONCLUSION: ECD in combination with HER2 CTC status would deserve further investigation in larger series for addressing its putative prognostic relevance.

Portal vein-circulating tumor cells predict liver metastases in patients with resectable pancreatic cancer.

Pancreatic cancer patients underwent surgical resection often present distant metastases early after surgery. Detection of circulating tumor cells (CTCs) has been correlated to a worse oncological outcome in patients with advanced pancreatic cancer. The objective of this pilot study is to investigate the possible prognostic role of CTCs in patients undergoing surgery for pancreatic cancer. In 20 patients undergoing pancreatic resection, 10 mL blood sample was collected intraoperatively from both systemic circulation (SC) and portal vein (PV). Blood sample was analyzed for CTCs with CellSearch® system. All patients underwent an oncologic follow-up for at least 3 years, quarterly. CTCs were detected in nine (45%) patients: five patients had CTCs in PV only, three patients in both SC and PV, and one patient in SC only. CTC-positive and CTC-negative patients were similar for demographics and cancer stage pattern. No significant differences were found in both overall and disease-free survival between CTC-positive and CTC-negative patients. At 3-year follow-up, portal vein CTC-positive patients presented a higher rate of liver metastases than CTC-negative patients (53 vs. 8%, p = 0.038). CTCs were found in 45% of the patients. No correlation between CTCs and survival was found. The presence of CTCs in portal vein has been associated to higher rate of liver metastases after surgery.

Molecular profiling of single circulating tumor cells with diagnostic intention.

Several hundred clinical trials currently explore the role of circulating tumor cell (CTC) analysis for therapy decisions, but assays are lacking for comprehensive molecular characterization of CTCs with diagnostic precision. We therefore combined a workflow for enrichment and isolation of pure CTCs with a non-random whole genome amplification method for single cells and applied it to 510 single CTCs and 189 leukocytes of 66 CTC-positive breast cancer patients. We defined a genome integrity index (GII) to identify single cells suited for molecular characterization by different molecular assays, such as diagnostic profiling of point mutations, gene amplifications and whole genomes of single cells. The reliability of > 90% for successful molecular analysis of high-quality clinical samples selected by the GII enabled assessing the molecular heterogeneity of single CTCs of metastatic breast cancer patients. We readily identified genomic disparity of potentially high relevance between primary tumors and CTCs. Microheterogeneity analysis among individual CTCs uncovered pre-existing cells resistant to ERBB2-targeted therapies suggesting ongoing microevolution at late-stage disease whose exploration may provide essential information for personalized treatment decisions and shed light into mechanisms of acquired drug resistance.

Detection of circulating tumor cells in patients with locally advanced rectal cancer undergoing neoadjuvant therapy followed by curative surgery.

PURPOSE: Circulating tumor cells (CTCs) represent an independent prognostic factor in metastatic colorectal cancer, while their significance in early stages is still an open issue. The aim of the study is to investigate the role of CTCs in rectal cancer patients undergoing neoadjuvant chemoradiotherapy (CT-RT). METHODS: In this prospective single institutional study, cT3-4 and/or N+ rectal cancer was treated with neoadjuvant CT-RT. The primary endpoints were as follows: evaluation of CTCs at baseline (t0), after CT-RT (t1), within 7 days after surgery (t2), and at 6 months from surgery (t3) and correlation with main patient/tumor characteristics, CEA, response to neoadjuvant therapy, and disease-free survival (DFS). CTCs were enumerated with the CellSearch System in 22.5 ml peripheral blood. A repeated measure analysis for binary outcome was used to evaluate over time changes in the percentage of CTCs detectable in blood samples. RESULTS: Of the 90 patients enrolled in this study, 85 were eligible consisting of 52 males and 33 females. Median age was 63 years and median follow-up was 38 months. CTCs were available for all patients at t0, for 67 at t1, for 68 at t2, and for 62 at t3. CTCs >0 were reported on 16 (19%) at t0, on 5 (7.5%) at t1, on 6 (9%) at t2, and on 3 (5%) at t3 (P value for trend 0.039). Only for CT-RT responders, CTCs reduced from t0 to t1. No statistically significant association was found between CTCs and main patient/tumor characteristics and DFS. CONCLUSIONS: Sixteen patients (19%) had CTCs ≥1 at t0 with reduction in CTC number in case of objective remissions. The proportion of patients with CTCs ≥1 decreased over the time as the therapeutic course proceeded. Much effort should be oriented toward increasing CTC detection rate by enhancing technical tests and achieving better patient characterization.

International study on inter-reader variability for circulating tumor cells in breast cancer.

INTRODUCTION: Circulating tumor cells (CTCs) have been studied in breast cancer with the CellSearch® system. Given the low CTC counts in non-metastatic breast cancer, it is important to evaluate the inter-reader agreement. METHODS: CellSearch® images (N = 272) of either CTCs or white blood cells or artifacts from 109 non-metastatic (M0) and 22 metastatic (M1) breast cancer patients from reported studies were sent to 22 readers from 15 academic laboratories and 8 readers from two Veridex laboratories. Each image was scored as No CTC vs CTC HER2- vs CTC HER2+. The 8 Veridex readers were summarized to a Veridex Consensus (VC) to compare each academic reader using % agreement and kappa (κ) statistics. Agreement was compared according to disease stage and CTC counts using the Wilcoxon signed rank test. RESULTS: For CTC definition (No CTC vs CTC), the median agreement between academic readers and VC was 92% (range 69 to 97%) with a median κ of 0.83 (range 0.37 to 0.93). Lower agreement was observed in images from M0 (median 91%, range 70 to 96%) compared to M1 (median 98%, range 64 to 100%) patients (P < 0.001) and from M0 and <3CTCs (median 87%, range 66 to 95%) compared to M0 and ≥3CTCs samples (median 95%, range 77 to 99%), (P < 0.001). For CTC HER2 expression (HER2- vs HER2+), the median agreement was 87% (range 51 to 95%) with a median κ of 0.74 (range 0.25 to 0.90). CONCLUSIONS: The inter-reader agreement for CTC definition was high. Reduced agreement was observed in M0 patients with low CTC counts. Continuous training and independent image review are required.

TnI-Ultra assay measurements in cancer patients: comparison with the conventional assay and clinical implication.

The serial monitoring of cardiac troponin represents an effective approach for the early identification, assessment, and monitoring of chemotherapy-induced cardiac injury. Over the last few years new generations of troponin assays, referred to as sensitive and high sensitivity assays, able to detect very low concentrations of troponin, have been progressively released on different platforms. Some studies have assessed the comparability of the cTnI measurements with the new assays versus the conventional ones, but none of these in the oncological population. We compared the cTnI results determined on Stratus CS and ADVIA Centaur CP System in 70 breast cancer patients, for a total of 327 samples collected during different cycles of treatment. Correlation (Spearman = 0.732) and agreement (91.4%) between the assays were good (244 concordant negatives and 55 concordant positives), with a frequency of 8.6% discordant results among the cTnI measurements. Despite the well-known lack in the harmonization and standardization of the currently commercially available cTnI methods, we found a good clinical concordance of cTnI determination on both systems.

Clinical validity of circulating tumour cells in patients with metastatic breast cancer: a pooled analysis of individual patient data.

BACKGROUND: We aimed to assess the clinical validity of circulating tumour cell (CTC) quantification for prognostication of patients with metastatic breast cancer by undertaking a pooled analysis of individual patient data. METHODS: We contacted 51 European centres and asked them to provide reported and unreported anonymised data for individual patients with metastatic breast cancer who participated in studies between January, 2003, and July, 2012. Eligible studies had participants starting a new line of therapy, data for progression-free survival or overall survival, or both, and CTC quantification by the CellSearch method at baseline (before start of new treatment). We used Cox regression models, stratified by study, to establish the association between CTC count and progression-free survival and overall survival. We used the landmark method to assess the prognostic value of CTC and serum marker changes during treatment. We assessed the added value of CTCs or serum markers to prognostic clinicopathological models in a resampling procedure using likelihood ratio (LR) χ(2) statistics. FINDINGS: 17 centres provided data for 1944 eligible patients from 20 studies. 911 patients (46·9%) had a CTC count of 5 per 7·5 mL or higher at baseline, which was associated with decreased progression-free survival (hazard ratio [HR] 1·92, 95% CI 1·73-2·14, p<0·0001) and overall survival (HR 2·78, 95% CI 2·42-3·19, p<0·0001) compared with patients with a CTC count of less than 5 per 7·5 mL at baseline. Increased CTC counts 3-5 weeks after start of treatment, adjusted for CTC count at baseline, were associated with shortened progression-free survival (HR 1·85, 95% CI 1·48-2·32, p<0·0001) and overall survival (HR 2·26, 95% CI 1·68-3·03) as were increased CTC counts after 6-8 weeks (progression-free survival HR 2·20, 95% CI 1·66-2·90, p<0·0001; overall survival HR 2·91, 95% CI 2·01-4·23, p<0·0001). Survival prediction was significantly improved by addition of baseline CTC count to the clinicopathological models (progression-free survival LR 38·4, 95% CI 21·9-60·3, p<0·0001; overall survival LR 64·9, 95% CI 41·3-93·4, p<0·0001). This model was further improved by addition of CTC change at 3-5 weeks (progression-free survival LR 8·2, 95% CI 0·78-20·4, p=0·004; overall survival LR 11·5, 95% CI 2·6-25·1, p=0·0007) and at 6-8 weeks (progression-free survival LR 15·3, 95% CI 5·2-28·3; overall survival LR 14·6, 95% CI 4·0-30·6; both p<0·0001). Carcinoembryonic antigen and cancer antigen 15-3 concentrations at baseline and during therapy did not add significant information to the best baseline model. INTERPRETATION: These data confirm the independent prognostic effect of CTC count on progression-free survival and overall survival. CTC count also improves the prognostication of metastatic breast cancer when added to full clinicopathological predictive models, whereas serum tumour markers do not. FUNDING: Janssen Diagnostics, the Nuovo-Soldati foundation for cancer research.

Detection of squamous cell carcinoma antigen with two systems in the follow-up of patients with cervical cancer.

Since squamous cell carcinoma antigen (SCC-Ag) testing became commercially available on the Architect platform, the previously established method on the Abbott IMx platform has been progressively replaced. Aim of this work was to compare SCC-Ag values obtained with the 2 methods. Clinical and laboratory data of 188 patients for whom SCC-Ag determination was requested, were reviewed. IMx was used to determine the levels of SCC-Ag from June 2007 to May 2009, while the Architect system was used from June 2009 to April 2011. Only patients consistently diagnosed with no evidence of disease, for whom at least 2 determinations with each analyzer were available were used. Comparison of the results obtained with the 2 systems was then performed. Mean values for SCC-Ag were 0.56 ng/mL (Standard Error (SE): 0.08) with the IMx method, and 1.08 ng/mL (SE 0.10) with Architect (p<0.0001). False positive results were found in 4.8% of patients with the IMx method and in 9.5% of patients with Architect (p=0.049). The values of SCC-Ag determined on the Architect platform are higher than those obtained on the IMx, with a higher percentage of false positive results.

Prognostic value of circulating tumor cells according to immunohistochemically defined molecular subtypes in advanced breast cancer.

BACKGROUND: Breast cancer is a heterogeneous disease. Circulating tumor cell (CTC) enumeration might be useful to identify different risk categories within each molecular subtype. METHODS: We 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). RESULTS: Median 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. CONCLUSION: These 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.

The pitfalls of CA19-9: routine testing and comparison of two automated immunoassays in a reference oncology center.

We evaluated CA19-9 as a marker of various malignancies and compared the results of 2 commercial immunoassays. The Abbott ARCHITECT i2000 and Roche cobas 410 immunoassays were used on 500 consecutive samples to evaluate the frequency of positive results by cancer type and the correlation between assays. The patients were tested before or after surgery and/or during chemotherapy. The rate of results exceeding conventional thresholds was 92.3% in pancreatic cancer, 36.8% in gastric cancer, and ranged from 3.0% to 35.9% in other tumors. Agreement (90.6%) and correlation (R(2) = 0.865) between the 2 assays were good and the frequency of highly discordant results was low (6/500). In some cases, interference by heterophilic antibodies was demonstrated. The 2 methods were comparable in diagnostic accuracy and had good correlation but are not interchangeable. Patients should always be monitored for CA19-9 with the same method and it should be indicated in the report.

Neuroendocrine differentiation in castration-resistant prostate cancer: a systematic diagnostic attempt.

BACKGROUND: Assessing the neuroendocrine (NE) pattern in castration-resistant prostate cancer (CRPC) may prove useful in selecting potential responders to target therapies such as somatostatin analogues. The aim of this study was to define a panel of markers or examinations appropriate to characterize NE differentiation (NED). METHODS: Forty-seven patients with CRPC underwent a systematic diagnostic attempt to characterize the NE phenotype using a plasma blood test for chromogranin A (CgA) and immunohistochemical staining of needle biopsy-obtained specimens (CgA, somatostatin receptor 2 [SSTR2], Ki-67, and androgen receptors). In a subgroup of 26 patients, somatostatin receptor scintigraphy using (111)In-DTPA-d-Phe octreotide (octreotide scintigraphy; Octreoscan, Covidien, Hazelwood, MO) was also performed. RESULTS: NED was found in 85.1% of patients (if serum CgA, tissular CgA, and tissular SSTR2 were considered separately: 54%, 67%, and 58%, respectively). Only 15% of the 26-patient subgroup had an abnormal octreotide scintigraphy result. Although p-CgA and t-CgA were associated with more aggressive disease with a worse prognosis, patients with positive tissular SSTR2 staining had longer overall survival (OS). CONCLUSION: This systematic approach to explore the NED in a quite homogeneous group of patients with CRPC seems reproducible and appropriate. Further investigations are required to validate this panel and better characterize potential responders to targeted therapy.

Prognostic value of circulating tumor cells in primary and metastatic breast cancer.

In patients with breast cancer, there is evidence correlating the presence of circulating tumor cells (CTCs) with disease-free survival, progression-free survival and overall survival. The detection of CTCs may be useful in gaining a better understanding of the mechanisms of tumor growth and in the improvement of patient management. This review analyzes the prognostic and predictive relevance of CTCs through the principal published studies, cytometric techniques and nucleic acid-based approaches to detect CTCs, phenotypic expression of specific receptors, molecular pathways and genetic signatures for potential tailored therapies.

Comparison of three distinct methods for the detection of circulating tumor cells in colorectal cancer patients.

The detection of circulating tumor cells (CTCs) has considerable utility in the clinical management of patients with solid cancers. However, the phenotypic heterogeneity of CTCs and their low numbers in the bloodstream of patients means that no standardized detection method currently exists for these cells. This, together with differences in pre-analytical sample processing, has led to the collection and accumulation of inconsistent data among independent studies. Here, we compare the ability of three methods to detect CTCs in the blood of colorectal cancer patients. Specifically, different aliquots of the same blood sample were screened for the presence of CTCs by a multimarker RT-PCR assay, the standardized CellSearch assay and dHPLC-based gene mutation analysis. In the population tested, none of the blood samples analysed appeared to be positive by all three methods. Of the samples, 75% were positive for the presence of CTCs by the RT-PCR method. Only 20% were positive by the CellSearch assay, while 14.3% of samples displayed gene mutations consistent with the presence of CTCs when the dHPLC method was applied. The samples which were positive for CTCs by the CellSearch assay did not overlap with those that were positive by dHPLC. Interestingly, however, all of these samples were positive when assessed by RT-PCR. Conversely, of the samples that resulted negative by RT-PCR analysis, none appeared to be positive by either of the other methods. These data, therefore, indicate that of the three methods tested, the multimarker RT-PCR assay provides maximal probability of CTC detection. Here, we present the preliminary results of an ongoing clinical study. Future follow-up involving detection of CTCs in the blood of colorectal cancer patients using these three distinct methods will allow us to verify whether either a single method, or a combination of different assays, is necessary to uncover further prognostic significance of circulating tumor cells.

External quality assurance of circulating tumor cell enumeration using the CellSearch(®) system: a feasibility study.

BACKGROUND: Circulating tumor cells (CTCs) are cells that have detached from solid tumors and entered the blood. CTCs can be detected, among others, by semi-automated immunomagnetic enrichment and image cytometry using CellSearch® (Veridex, Raritan, NJ). We studied the feasibility of external quality assurance (EQA) of the entire CellSearch procedure from blood draw to interpretation of results in multiple laboratories. METHODS: Blood samples from six cancer patients and controls were distributed to 14 independent laboratories to test between-laboratory, between-assay, and between-instrument variation. Additionally, between-operator variability was assessed through the interpretation of blinded images of all blood samples on a website. RESULTS: Shipment and storage of samples had no influence on CTC values. Between-instrument (coefficient of variation (CV) < 12%) and between-assay variation was low (CV ≤ 20%), indicating high reproducibility. However, between-laboratory CV ranged from 45 to 64%. Although inter-operator agreement on image interpretation (Fleiss' κ statistics) ranged from "substantial" to "almost perfect," image interpretation, particularly of samples containing high numbers of apoptotic cells, was the main contributor to between-laboratory variation. CONCLUSIONS: This multicenter study shows the feasibility of an EQA program for CTC detection in patient samples, and the importance of continuation of such a program for the harmonization of CTC enumeration.

Changes of HER2 status in circulating tumor cells compared with the primary tumor during treatment for advanced breast cancer.

BACKGROUND: HER2/neu status of tumor cells at metastatic sites in patients with advanced disease may differ from that of the primary tumor. Assessing the presence of target antigens on circulating tumor cells (CTCs) might affect treatment choice. PATIENTS AND METHODS: From June 2007 to October 2008, we collected 23 mL of blood from each of the 76 consecutive patients before and during chemotherapy to determine CTC numbers and HER2 overexpression. CTCs were isolated with the CellSearch System® (Veridex, LLC; Raritan, NJ) and fluorescently stained with the Epithelial Cell Kit®. Tumor Phenotyping Reagent® was used to investigate HER2/neu overexpression. RESULTS: Concordance of HER2 status between the primary tumor and CTCs was 86% (49 out of 57 patients) at baseline and 82% (50 out of 61 patients) in the treatment samples. HER2 overexpression in CTCs was acquired in 8 out of 45 patients (18%) and lost in 3 out of 16 patients (19%) during a treatment containing trastuzumab. The overall discordance rate between the primary tumor and CTCs was 18% (11 out of 61 patients). Patients with HER2 overexpression in CTCs had poorer progression-free survival compared with those without CTCs or with HER2- CTCs (log-rank P =.036). CONCLUSION: Information on the presence or absence of HER2 overexpression can be obtained in CTCs. Larger trials are needed to evaluate the activity of HER2-targeted therapy in patients with acquired HER2 overexpression in CTCs.