Detection of Circulating Tumor Cells Using a Novel Immunomagnetic Bead Method in Lung Cancer Patients

Prognostic value of detection of CD99+ , CD45- cells in peripheral blood by flow cytometry in children with Ewing sarcoma

BACKGROUND

Early detection of metastasis and recurrence of Ewing sarcoma (ES) is important for early management. This work aimed to detect CD99⁺ , CD45^- cells in peripheral blood by flow cytometry (FC) before and during chemotherapy and evaluate their prognostic significance.

PROCEDURE

This prospective cohort study was carried out on 60 children newly diagnosed with ES at Children Cancer Hospital-Egypt 57357 and 40 healthy children control group. Detection of CD99⁺ , CD45^- cells in peripheral blood was accomplished by FC at baseline before treatment and after five cycles of chemotherapy. Samples were classified as positive if they had more than the upper limit of cells observed in the control cases. Correlation between FC results and relapse and overall survival (OS) after one year was performed.

RESULTS

Median percentage of CD99⁺ , CD45^- cells was significantly increased in patients compared with controls (0.002% vs 0%, respectively, P < 0.001). Post-cycle 5 CD99⁺ , CD45^- cells were increased in 12 patients, of them 11 patients' disease had either relapsed or progressed. Post-cycle 5 CD99⁺ ; CD45^- cells had a 73.3% sensitivity and 97.8% specificity for predicting relapse or progression, whereas baseline only had 6.7% sensitivity and 77.8% specificity. The hazard ratio for mortality in the post-cycle 5 positive group was 18.4 [95% confidence interval (1.86 to 181.46)] times that of the negative group. One year OS was 91.67%.

CONCLUSION

Post-cycle 5 CD99⁺ , CD45^- cells in peripheral blood by FC is a strong predictor for relapse, progression, and mortality whereas baseline is a poor predictor in newly diagnosed patients with ES.

Identification of elastofibroma and elastofibroma-like lesions in cases diagnosed as oral fibromas

We investigated elastofibromas (EF) and elastofibroma-like structures (EFL) in 95 cases that had been diagnosed as oral fibromas (OF). Histological sections were stained with Verhoeff-Van Gieson, Congo red and hematoxylin and eosin to enable possible reclassification to EF or EFL, or to retain the diagnosis of OF. To do this, we identified amyloid and used histopathological descriptions and epidemiological clinical profiles. We found 56 EF and 21 EFL cases, while 18 diagnoses of OF were retained. We observed a predilection for EF in females. Also, the most common site for OF was the cheek mucosa. We also found a longer time course for lesion development for OF compared to the other lesions. We found a relation between elastic fibers and amyloid material in EF. We also observed perivascular fibrotic lesions (PVFL) in EF. Most cases of EF exhibited more elastic fibers, thicker fibers, stronger relation with amyloid material deposition, rare evidence of PVFL and a longer time course for development compared to the other lesions. We suggest that EFL may give rise to oral EF.

Detection of circulating tumor cells in liquid biopsy from Ewing sarcoma patients

Background

Circulating tumor cells (CTCs) analysis is a promising new diagnostic field to estimate risk and monitor treatment efficacy, metastatic relapse, and progression in cancer patients. The study aim was to isolate and characterize CTCs in blood samples of Ewing sarcoma (ES) patients exploiting two main characteristics: CD99 expression and presence of chromosomal translocations.

Materials and methods

The method isolated CTCs from peripheral blood (PB) of ES patients. Cell-surface CD99 was a useful marker for CTCs determined using immunomagnetic separation with microbeads and CD99 monoclonal antibody. We tested sensitivity and specificity by detecting CTCs in blood collected from healthy donors and randomly during therapy from 18 ES patients. Evidence of CTCs was confirmed by detection of specific molecular markers using quantitative and digital reverse transcription-polymerase chain reaction targeting EWSR1/FLI1 type 1 and type 2 or EWSR1/ETS-related gene transcripts type 1 and type 9e.

Results

Feasibility of finding CTCs in PB of ES patients by immunoseparation with CD99 antibody and magnetic microbeads was demonstrated for the first time. At molecular analysis, three PB specimens tested positive for chimeric EWSR1/FLI1 type 2 and one PB for chimeric EWSR1/FLI1 type 2. CTCs detection was found above a limit of detection of 1 cell/mL of PB.

Conclusion

CTCs in PB of ES patients can be identified by this method and in ES CTCs analysis can be used as a liquid biopsy approach for prognostic and predictive purposes. The potential clinical implications of CTCs in PB samples detected by the platform for CTC isolation with molecular confirmation during therapy require further evaluation.

Molecular characterization of circulating tumor cells in lung cancer: moving beyond enumeration

Molecular characterization of tumor cells is a key step in the diagnosis and optimal treatment of lung cancer. However, analysis of tumor samples, often corresponding to small biopsies, can be difficult and does not accurately reflect tumor heterogeneity. Recent studies have shown that isolation of circulating tumor cells (CTCs) is feasible in non-small cell lung cancer patients, even at early disease stages. The amount of CTCs corresponds to the metastatic potential of the tumor and to patient prognosis. Moreover, molecular analyses, even at the single-cell level, can be performed on CTCs. This review describes the technologies currently available for detecting and capturing CTCs, the potential for downstream molecular diagnostics, and the clinical applications of CTCs isolated from lung cancer patients as screening, prognostic, and predictive tools. Main limitations of CTCs are also discussed.

Clinicopathological and prognostic significance of circulating tumor cells in patients with lung cancer: a meta-analysis

BACKGROUND

The prognostic significance of circulating tumor cells in patients with lung cancer is controversial. Therefore, we aimed to comprehensively and quantitatively assess the prognostic role of CTCs in patients with lung cancer.

METHODS

The relevant literature was searched using PubMed, the Cochrane database and the China National Knowledge Internet database (up to June 2016). Using Review Manager 5.1.2, a meta-analysis was performed using hazard ratio (HR), odds ratio (OR) and 95% confidence interval (CI) as effect values.

RESULTS

Thirty studies comprising 2,060 patients with lung cancer were analyzed. The pooled HR values showed that circulating tumor cells were significantly correlated with overall survival (HR =2.63, 95% CI [2.04, 3.39]) and progression-free survival (HR =3.74, 95% CI [2.49, 5.61]) in these patients. Further subgroup analyses were conducted and categorized by sampling time, detection method, and histological type; these analyses showed the same trend. The pooled OR values showed that circulating tumor cells were associated with non small cell lung cancer stage(OR = 2.11, 95% CI [1.42, 3.14]), small cell lung cancer stage (OR = 10.91, 95% CI [4.10, 29.06]), distant metastasis (OR =7.06, 95%CI [2.82, 17.66]), lymph node metastasis (OR =2.31, 95% CI [1.19,4.46]), and performance status(OR =0.42, 95%CI [0.22, 0.78]).

CONCLUSION

The detection of circulating tumor cells in the peripheral blood of patients with lung cancer can be indicative of a poor prognosis.