Positive peritoneal cytology predicts unresectability of pancreatic adenocarcinoma

Background: Peritoneal cytology is clinically useful in gastric and gynecol ogic malignancies. Its role in pancreatic adenocarcinoma remains less well defined. Controversy exists as to the relationship between percutaneous fin e needle aspiration (FNA) of the pancreas and shedding of malignant cells w ith the peritoneum. The aim of this study was to determine whether positive peritoneal cytology (PPC) predicts unresectability of pancreatic adenocarc inoma and impacts on overall survival. In addition, the study aimed to dete rmine whether antecedent FNA increases the incidence of PPC. Study Design: Between January 1993 and June 1996, 228 patients with radiogr aphically resectable pancreatic adenocarcinoma underwent laparoscopic stagi ng. Specimens were taken from right and left upper quadrants at the beginni ng of laparoscopy. Various prognostic factors were analyzed, Results: PPC was identified in 34 patients (15%). Of patients that had an a ntecedent FNA, 20% had PPC, and 13% of those without an antecedent FNA had PPC (p = 0.22). The majority of patients with PPC had stage IV disease (26 of 34 [76%]) and only 8 (24%) had no evidence of metastase. Overall surviva l was significantly higher in patients with negative peritoneal cytology (N PC) compared with PPC (p < 0.0006). PPC had a positive predictive value of 94.1%, specificity of 98.1%, and a sensitivity of 25.6% for determining unr esectability of pancreatic adenocarcinoma. PPC was not an independent progn ostic variable for survival on multivariate analysis. Conclusions: PPC is associated with advanced disease and is highly specific in predicting unresectability of pancreatic adenocarcinoma, resulting in d ecreased survival. Antecedent FNA is not associated with an increased the i ncidence of PPC, nor does it significantly impact on overall survival. (J A m Coil Surg 1999;188: 421-426. (C) 1999 by the American College of Surgeons ).