Circulating Tumor Cells in Lung Cancer Screening

Thirty ml of peripheral blood will be collected in buffered EDTA, maintained at 4°C, and processed within 1 hour for filtration. After blood filtration, the membrane will be gently washed with PBS, disassembled from the filtration module, and allowed to air-dry. The determination of CTC number present on filters will be carried out by combining four color immunofluorescent (anti-pancytokeratins/anti-vimentin/DAPI/anti-CD45) staining and cytomorphological examination after Diff-quick and Mayer Hemalun staining in three spots per patient sample. Imaging of immunofluorescent and cytological staining will be performed at x20 magnification using the automated Ariol system. CTCs are identified by relocating images of immunofluorescent and cytological staining.