Laparoscopic peritoneal lavage cytology and immunocytology in pancreatic and periampullary carcinoma.

BACKGROUND Free tumour cells in the peritoneal cavity of patients with pancreatic carcinoma carry a poor prognosis. Reactive or degenerative mesothelial cells can make cytological interpretation with conventional stains difficult. Detection of the tumour-associated antigens carcinoembryonic antigen (CEA) and CA19-9 may improve detection. METHODS At staging laparoscopy, 22 patients with pancreatic or periampullary tumours had ascitic fluid aspirated or peritoneal lavage performed. Both conventional and immunocytologically stained preparations were examined. Antibodies to CEA and CA19-9 and the epithelial marker BerEP4 were used. Lavage fluid from ten patients having operative treatment for benign pancreatic or biliary conditions was also examined. RESULTS No malignant cells on conventional cytological criteria were recovered.Thirteen of the 22 patients with pancreatic or periampullary carcinoma had peritoneal cells that were positive for CEA and/or CA19-9. None was positive for BerEP4. No patients with resectable disease had cells that were positive for CEA or CA19-9 compared with 13 of 18 (72%) who had unresectable disease. One patient (10%) with benign disease (chronic pancreatitis) had cells recovered that were weakly positive for CEA but negative for CA19-9 and BerEP4. DISCUSSION Recovery of cells from the peritoneal cavity of patients with pancreatic or periampullary carcinoma that are expressing the tumour-associated antigens CEA or CA19-9 does not indicate the presence of free tumour cells but is associated with advanced disease.