DISTRIBUTION OF TYPE-IV COLLAGEN IN PANCREATIC ADENOCARCINOMA AND CHRONIC-PANCREATITIS

Changes in the basement membrane are present in various neoplastic con ditions such as neurofibrosarcoma, cervical carcinoma, colorectal canc ers and hepatoblastoma. This study examines the expression of type IV collagen in the basement membrane, using an immunohistochemical method , in the normal pancreas (n=10), chronic pancreatitis (n=15) and pancr eatic adenocarcinoma (n=30). The formalin fixed, paraffin embedded tis sue was sectioned and pretreated with protease prior to immunostaining for type IV collagen. There was a statistically significant differenc e in type IV collagen expression between pancreatic carcinoma and chro nic pancreatitis (P=0.0001; (2)(chi) test with continuity correction). In pancreatic adenocarcinoma, type IV collagen distribution in the ba sement membrane was discontinuous and irregular or absent around indiv idual or groups of neoplastic cells (n=30). Most cases of chronic panc reatitis showed continuous pattern of basement membrane type IV collag en around residual ducts (n=10). In the normal pancreas, only one of t he ten cases showed discontinuous basement membrane around pancreatic ducts, while in the rest of the cases, the pattern was continuous. Thi s study suggests that there is abnormal distribution of type IV collag en in the basement membrane in pancreatic carcinoma, which may be rela ted to either abnormal deposition or degradation of the collagen. Immu nostaining for type IV collagen may be of some diagnostic use for dist inguishing pancreatic adenocarcinoma from problematic cases of chronic pancreatitis.