IMMUNOCYTOCHEMICAL DETECTION OF P53 PROTEIN AS AN ADJUNCT IN CYTOLOGIC DIAGNOSIS FROM PANCREATIC DUCT BRUSHINGS IN MUCIN-PRODUCING TUMORS OF THE PANCREAS

BACKGROUND, In cases of mucin-producing tumor (MPT) of the pancreas, a new clinical entity of pancreatic tumor, it has been reported to be d ifficult to distinguish adenoma from carcinoma preoperatively. This ob servation caused the authors to develop a new method of p53 immunocyto chemistry using cytologic samples obtained by endoscopic retrograde pa ncreatic duct brushing (ERPDB). METHODS, Fifteen cases of MPT (9 with carcinoma and 6 with adenoma) were examined. In all cases, histologic diagnosis was determined by surgery or autopsy. A wire with a small br ush was pushed into the dilatated pancreatic duct detected by endoscop ic retrograde pancreatography (ERP). Specimens obtained by brushing we re prepared on slides and subsequently fixed with ethanol. Papanicolao u staining and p53 immunocytochemistry were performed simultaneously. The ability of conventional cytology to distinguish adenoma from carci noma was compared with that of p53 immunocytochemistry. RESULTS, Five of 9 cases (36%) with carcinoma of MPT were correctly diagnosed by Pap anicolaou staining. Two of four cases, classified as benign by Papanic olaou staining, expressed p53 protein. Overall, 7 of 9 cases (78%) wit h carcinoma MPT were correctly diagnosed by Papanicolaou staining asso ciated with p53 immunocytochemistry. In the cases with adenoma MPT, al l cases were classified as benign by Papanicolaou staining and no case positive for p53 protein was encountered. CONCLUSIONS, These results suggest that p53 immunocytochemistry as an adjunct in cytologic diagno sis using ERPDB may contribute to differentiating adenoma from carcino ma MPT of the pancreas preoperatively. (C) 1997 American Cancer Societ y.