Background: Our aim was to assess the expression profiles of the messenger RNA (mRNA) expression profiles of stem-cell genes (POU5F1, NANOG) and pancreatic progenitor genes (CK19, HES1, INS, PDX1) in peripheral-blood mononuclear cells (PBMCs) in selected neoplastic pancreatic diseases, such as cancer and neuroendocrine tumors, to identify neoplastic disease markers in the pancreas. The gene discussed is POU5F1; the disease is cancer.