Proliferation index and karyometric features of pancreatic intraductal proliferative lesions

The increasing frequency and poor prognosis in pancreatic cancer prompt us to search for morphological lesions being a substrate for its development. Studies of autopsy and surgically resected material as well as recent molecular studies have proved that one of the possible pathways of pancreatic neoplasia is the intraepithelial proliferation--dysplasia--cancer sequence. In the present paper we studied the proliferative activity (Ki-67 index) in pancreatic intraepithelial proliferative lesions and its correlation with geometric features of cell nuclei as signs of increasing dysplasia. The studies were carried out in a group of 35 patients operated on for pancreatic cancer, chronic pancreatitis and other conditions not associated with the pancreas. We used immunohistochemical methods and basic morphometric parameters. The results of our studies indicate that the cell proliferative activity depends both on the type of epithelial proliferation and underlying pancreatic disease. The values of Ki-67 index are significantly different in low-grade proliferation (flat and papillary hyperplasia) and high-grade proliferation (atypical papillary hyperplasia and carcinoma in situ). A set of karyometric features correlates with Ki-67 index but there is no single feature which would have a diagnostic value.