title: The Challenges of Detecting Circulating Tumor Cells in Sarcoma.
abstract: Sarcomas are a heterogeneous group of malignant neoplasms of mesenchymal origin, many of which have a propensity to develop distant metastases. Cancer cells that have escaped from the primary tumor are able to invade into surrounding tissues, to intravasate into the bloodstream to become circulating tumor cells (CTCs), and are responsible for the generation of distant metastases. Due to the rarity of these tumors and the absence of specific markers expressed by sarcoma tumor cells, the characterization of sarcoma CTCs has to date been relatively limited. Current techniques for isolating sarcoma CTCs are based on size criteria, the identification of circulating cells that express either common mesenchymal markers, sarcoma-specific markers, such as CD99, CD81, or PAX3, and chromosomal translocations found in certain sarcoma subtypes, such as EWS-FLI1 in Ewing's sarcoma, detection of osteoblast-related genes, or measurement of the activity of specific metabolic enzymes. Further studies are needed to improve the isolation and characterization of sarcoma CTCs, to demonstrate their clinical significance as predictive and/or prognostic biomarkers, and to utilize CTCs as a tool for investigating the metastatic process in sarcoma and to identify novel therapeutic targets. The present review provides a short overview of the most recent literature on CTCs in sarcoma.
authors.affiliation: UMR 957, Pathophysiology of Bone Resorption and Therapy of Primary Bone Tumours, Equipe Ligue 2012, Faculty of Medicine, INSERM, University of Nantes, Nantes, France; Laboratotio Hematologia Oncologica y de Transplantes, Institut Investigacions Biomèdiques (IBB) Sant Pau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Tellez-Gabriel
authors.affiliation: Department of Oncology and Metabolism, Medical School, University of Sheffield, Sheffield, UK; European Associated Laboratory, INSERM-University of Sheffield, Sarcoma Research Unit, Medical School, Sheffield, UK.
authors.forename: Hannah K
authors.initials: HK
authors.lastname: Brown
authors.affiliation: Department of Oncology and Metabolism, Medical School, University of Sheffield, Sheffield, UK; European Associated Laboratory, INSERM-University of Sheffield, Sarcoma Research Unit, Medical School, Sheffield, UK.
authors.forename: Robin
authors.initials: R
authors.lastname: Young
authors.affiliation: UMR 957, Pathophysiology of Bone Resorption and Therapy of Primary Bone Tumours, Equipe Ligue 2012, Faculty of Medicine, INSERM, University of Nantes, Nantes, France; Department of Oncology and Metabolism, Medical School, University of Sheffield, Sheffield, UK; European Associated Laboratory, INSERM-University of Sheffield, Sarcoma Research Unit, Medical School, Sheffield, UK; Nantes University Hospital, Nantes, France.
authors.forename: Marie-Françoise
authors.initials: MF
authors.lastname: Heymann
authors.affiliation: UMR 957, Pathophysiology of Bone Resorption and Therapy of Primary Bone Tumours, Equipe Ligue 2012, Faculty of Medicine, INSERM, University of Nantes, Nantes, France; Department of Oncology and Metabolism, Medical School, University of Sheffield, Sheffield, UK; European Associated Laboratory, INSERM-University of Sheffield, Sarcoma Research Unit, Medical School, Sheffield, UK; Nantes University Hospital, Nantes, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Heymann
keywords: cancer stem cells; circulating tumor cells; neuroblastoma; rare cancers; sarcoma