CD4 and non-small cell lung carcinoma: To identify and compare CK+ and immune cell types in (i) primary tumors from early-stage NSCLC patients, and (ii) PE clinical specimens from late-stage NSCLC patients, we developed a mass cytometry panel with antibodies that were selected to identify epithelial cells along a spectrum EMT phenotypic states and five main immune populations, specifically: CD4+ T cells, CD8+ T cells, CD33+ Myeloid cells, CD56+ NK cells and CD20+ B cells.