Circulating Tumor Cells as an Auxiliary Diagnostic Tool in Surgery.

Background: In general, the presence of circulating tumor cells (CTCs) in peripheral blood (PB) is associated with a relative shorter overall survival in cancer patients. The clinical utility of CTC diagnostics is changing: from prognostic test to an assay predicting therapy response, enabling the right choice of therapy and monitoring the effect of administered therapy. We present two case reports of patients with suspicion of lung and pancreatic cancer, without obtainable preoperative biopsy for histological verification. The focus of the presented study was not to deliver a complete tumor tissue classification to the surgeon, but to answer the question if there is malignant disease or not. The results are based on CTC presence and characterization. Materials and Methods: A size-based separation method for viable CTC enrichment from anticoagulated PB was used. The separated cells were cytomorphologically examined using vital fluorescent microscopy. Additionally, to confirm the epithelial origin of the cells on the separation membrane, CTC gene expression analysis was performed. Results: CTCs were successfully enriched and cultured in vitro in both tested samples. The epithelial character of the captured cells was confirmed by quantitative-polymerase chain reaction (qPCR) analysis for a set of tumor-associated genes. Conclusion: Detection of cancer cells in PB (liquid biopsy) and their molecular characterization could significantly help complete the tumor diagnostic process in a time-efficient manner.