Immunohistochemical analysis of nestin and c-kit and their significance in pancreatic tumors.

The purpose of the present study was to clarify the difference of expression of two stem cell markers, nestin and c-kit, among various pancreatic epithelial tumors and evaluate their utility. Immunohistochemistry was done for 99 surgically resected pancreatic tumor specimens, including 20 ductal adenocarcinoma (DAC), two undifferentiated carcinomas (UC), 31 intraductal papillary-mucinous neoplasms (IPMN), six mucinous cystic neoplasms (MCN), five serous cystadenomas (SCA), six acinar cell carcinomas, two pancreatoblastoma (PB), eight solid-pseudopapillary neoplasms (SPN), and 19 endocrine neoplasms (EN). Nestin was widely expressed in four SPN, one PB, one SCA, sarcoma areas in two UC, one MCN, and one DAC, and an area of oncocytic component in one IPMN. Some of these SPN, SCA and sarcomatous or oncocytic components in which nestin was expressed, also coexpressed c-kit. Additionally, partial (scattered) expression of c-kit was observed in ductal elements of 16 DAC, eight IPMN, five MCN, and one UC, one SCA, and three EN. The eight c-kit-positive IPMN included four of 23 adenoma-to-border lesions and four of eight non-invasive-to-invasive carcinomas. The three EN were all carcinomas. These indicate that expression of two stem cell markers is different by tumor type, but the utility of judging direction or degree of differentiation and malignant grade on the basis of their expression status is suggested.