CD33 and neoplasm: We examined the pancreatic tumour tissue infiltrate for presence of myeloid cells and we assessed the expression of the same markers used to characterise circulating myeloid cells (Lin, HLA-DR, CD33, CD11b, CD14, and CD15) by flow cytometry in the tumour cell suspensions following enzymatic disaggregation (ED) of fresh surgically resected pancreatic tumour tissues of seven patients with stage I/II PC.