To investigate the histopathological characteristics of inverted papillomas of the urinary bladder, including the possibility of malignant transformation, we studied the indicators of cellular proliferation activity in 7 inverted papillomas of the bladder including two cases of malignant inverted papilloma of the bladder. PCNA expression rates in two cases of malignant inverted papilloma were higher than in benign inverted papillomas. Mean numbers of AgNORs per nucleus in malignant inverted papillomas were much more than in benign inverted papillomas. The c-erbB-2 oncoprotein was expressed only in malignant inverted papillomas. These results suggest that PCNA expression rate, mean number of AgNORs per nucleus and c-erB-2 oncoprotein expression may be merited as good indicators to detect the inverted papilloma with more proliferative and aggressive lesions, and with the potential of malignant transformation.
Adult ; Bladder Diseases/pathology ; Bladder Neoplasms/chemistry/*pathology ; Cell Division/physiology ; Cell Transformation, Neoplastic/pathology ; Female ; Human ; Male ; Middle Age ; Nitrosourea Compounds/analysis ; Nucleolus Organizer Region/chemistry ; Papilloma, Inverted/chemistry/*pathology ; Receptor, erbB-2/analysis ; Silver Staining

Fifteen cases of papillary cystic tumor of the pancreas (PCTP) were studied (14 female patients, one male patient; mean age: 23.5 years). Most tumors developed in the head of the pancreas as a well circumscribed large mass. The tumor had a mean diameter of 6.7 cm(range; 2 to 15 cm). Histopathologically abundant delicate papillary fragments, monomorphic tumor cells and degenerative changes of the solid area of the tumor were characteristic. All but two cases had completely circumscribed capsules. Two cases had duodenal invasion; one of all cases had cul de sac metastasis. Compared with 12 non-aggressive tumors, the aggressive cases had larger tumor size (more than 9 cm) with a thicker capsule (more than 2 mm). In studies to investigate the prognostic index using nucleolar organizing region (NOR), proliferating cell nuclear antigen (PCNA) and flow cytometry as well as nuclear grade and mitotic index, we could not find the useful parameter to detect the malignant potential of PCTP. In the flow cytometric analysis of cellular DNA contents, two invasive cases and the only one case of the male patient among the non-aggressive group were aneuploid. In conclusion, although it is hard to predict the prognosis by microscopic findings only, those with a thick capsule and aneuploidy tend to be related to malignant potential.
Adolescent ; Adult ; Cell Division/physiology ; Cystadenoma, Papillary/*chemistry/*pathology ; Female ; Flow Cytometry ; Human ; Immunohistochemistry ; Male ; Nucleolus Organizer Region/chemistry ; Pancreatic Cyst/*chemistry/*pathology ; Pancreatic Neoplasms/*chemistry/*pathology ; Predictive Value of Tests ; Prognosis ; Proliferating Cell Nuclear Antigen/analysis ; Silver Staining ; Support, Non-U.S. Gov't