[Pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasms (IPMN)].

Pancreatic Intraepithelial Neoplasia (PanIN1-3) and Intraductal Papillary Mucinous Neoplasms (IPMNs) putative precursors of and associated to pancreatic cancer represent a distinct, however pathologically heterogenous entity. Recently a new classification and nomenclature was established. We analysed the clinicopathologic and cytogenetic characteristics of six patients with PanIN and two with IPMN undergoing curative surgical resection. The most valuable tool in the diagnosis of these preinvasive neoplasms is ERCP combined with brush cytology. Conventional laboratory blood tests, tumor markers (CEA, CA19-9) were within normal values and imaging modalities were informative in only one third of the cases, however, not pathognostic. Based on our hypothesis that tumor ploidy pattern correlates with biological behaviour, malignant potential and prognosis, we measured the nuclear DNA content, ploidy, synthetic (S) phase or proliferative fractions of each neoplasm by flow cytometry. Each neoplasm demonstrated diploid stemline, with a low mean S-phase or proliferative fraction (3,77%) and mean DNA index (DI) of 0.96. The diploid DNA pattern and the low proliferative activity are consistent with the nonaggressive biological behavior of intraepithelial and intraductal neoplasms and, in part, explain their favorable prognosis.