Detection of disseminated tumor cells in aspirative drains after neck dissection

Study of the survival of patients with head and neck cancer in relation to Circulating Tumor Cells (CTCs)

Distant metastasis in head and neck cancer are one of the first factors contributing to death. Currently, it is difficult to detect them early with our conventional techniques such as Positron Emission Tomography scanner (PET-scanner) and Magnetic Resonance Imaging (MRI). Therefore, it is important to find new markers that can help us in the care of the patient. This study aimed at comparing two methods (Reverse Transcription-Polymerase Chain Reaction and CellSearch) to detect circulating tumor cells (CTC) as a prognosticator. Results were statistically significant for markers EphB4 (p-value =  0.0003), CEA (p-value =  0.0006), CK 18 (p-value =  0.0011) and Ep-CAM (p-value =  0.0299) and demonstrate that our detection techniques could be used by optimizing our protocol. In addition, results of the rate of CTCs helped identify this as an indicator of a prognosis for the patient. Indeed, the study revealed that most patients in remission exhibited a decrease in post-operative CTCs, whereas patients experiencing relapses demonstrated an increase in CTCs, which was correlated with a poor prognosis.

Nanomedical detection and downstream analysis of circulating tumor cells in head and neck patients

The establishment of novel biomarkers in liquid biopsies of cancer patients has come more into focus in prognostic and diagnostic research efforts. Due to their prognostic relevance disseminated tumor cells or circulating tumor cells are the subject of intensive research and are discussed as early diagnostic indicators for treatment failure and the formation of micrometastases. A potential association of this early-systemic tumor component with poor prognosis of cancer patients could be already demonstrated for various entities including breast, colon, lung, melanoma, ovarian and prostate cancers. Thus, the detection of circulating tumor cells seems to be also applicable for minimal-invasive monitoring of therapy progress in head and neck cancer patients. A major problem of the use in clinical routine is that circulating tumor cells could not be detected by modern imaging techniques. To overcome these limitations highly sensitive detection methods and techniques for their molecular characterization are urgently needed allowing mechanistic understanding and targeting of circulating tumor cells. Especially the medical application of nanotechnology (nanomedical methods) has made valuable contributions to the field. Here, we want to provide a comprehensive overview on (nanomedical) detection methods for circulating tumor cells and discuss their merits, pitfalls and future perspectives especially for head and neck solid squamous cell carcinoma (HNSCC) patients.

Circulating Tumor Cells as a Prognostic Factor in Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma: The CIRCUTEC Prospective Study

BACKGROUND

This prospective multicenter study evaluated the prognostic value of circulating tumor cells (CTCs) in relapsing nonoperable or metastatic head and neck squamous cell carcinoma (rHNSCC) treated by chemotherapy and cetuximab.

METHODS

In 65 patients suitable for analyses, peripheral blood was taken at day 0 (D0) D7, and D21 of treatment for CTC detection by CellSearch®, EPISPOT, and flow cytometry (FCM). Progression-free survival (PFS) was assessed with the Kaplan–Meier method and compared with the log-rank test (P < 0.05).

RESULTS

At D0, CTCs were detected with EPISPOT, CellSearch, and FCM in 69% (45/65), 21% (12/58), and 11% (7/61) of patients, respectively. In the patients tested with all 3 methods, EPISPOT identified 92% (36/39), 92% (35/38), and 90% (25/28) of all positive samples at D0, D7, and D21, respectively. Median PFS time was significantly lower in (a) patients with increasing or stable CTC counts (36/54) from D0 to D7 with EPISPOTEGFR (3.9 vs 6.2 months; 95% CI, 5.0–6.9; P = 0.0103) and (b) patients with ≥1 CTC detected with EPISPOT or CellSearch® (37/51) (P = 0.0311), EPISPOT or FCM (38/54) (P = 0.0480), and CellSearch or FCM (11/51) (P = 0.0005) at D7.

CONCLUSIONS

CTCs can be detected before and during chemotherapy in patients with rHNSCC. D0–D7 CTC kinetics evaluated with EPISPOTEGFR are associated with the response to treatment. This study indicates that CTCs can be used as a real-time liquid biopsy to monitor the early response to chemotherapy in rHNSCC.

ClinicalTrials.gov Identifier

NCT02119559

Clinical applications of the CellSearch platform in cancer patients

The CellSearch® system (CS) enables standardized enrichment and enumeration of circulating tumor cells (CTCs) that are repeatedly assessable via non-invasive "liquid biopsy". While the association of CTCs with poor clinical outcome for cancer patients has clearly been demonstrated in numerous clinical studies, utilizing CTCs for the identification of therapeutic targets, stratification of patients for targeted therapies and uncovering mechanisms of resistance is still under investigation. Here, we comprehensively review the current benefits and drawbacks of clinical CTC analyses for patients with metastatic and non-metastatic tumors. Furthermore, the review focuses on approaches beyond CTC enumeration that aim to uncover therapeutically relevant antigens, genomic aberrations, transcriptional profiles and epigenetic alterations of CTCs at a single cell level. This characterization of CTCs may shed light on the heterogeneity and genomic landscapes of malignant tumors, an understanding of which is highly important for the development of new therapeutic strategies.

Improving the CellSearch® system

INTRODUCTION

The CellSearch® CTC test enumerates tumor cells present in 7.5 ml blood of cancer patients. improvements, extensions and different utilities of the cellsearch system are discussed in this paper. Areas covered: This paper describes work performed with the CellSearch system, which go beyond the normal scope of the test. All results from searches with the search term 'CellSearch' from Web of Science and PubMed were categorized and discussed. Expert commentary: The CellSearch Circulating Tumor Cell test captures and identifies tumor cells in blood that are associated with poor clinical outcome. How to best use CTC in clinical practice is being explored in many clinical trials. The ability to extract information from the CTC to guide therapy will expand the potential clinical utility of CTC.

Circulating tumor cells in head and neck cancer: A review

Carcinoma of the head and neck represents 3.5% of all cancers, and the vast majority of these tumors are squamous cell carcinoma (HNSCC). With a stable overall survival rate of 50% among all stages, there is continued interested in developing measures for early detection and disease aggressiveness. Circulating tumor cells (CTCs) have been identified as a potential marker for early metastatic disease, response to treatment, and surveillance in head and neck squamous cell carcinoma. In this article, techniques of CTC detection, applications of CTC technology, and outcomes of HNSCC patients will be discussed.