Intraoperative Peritoneal Washing Cytology on Survival in Pancreatic Ductal Adenocarcinoma With Resectable, Locally Advanced, and Metastatic Disease.

Abstract

The prognostic implications of intraoperative peritoneal washing cytology (IPWC) in patients with pancreatic ductal adenocarcinoma (PDAC) remains incompletely understood. A meta-analysis was conducted to investigate the impact of IPWC status on the clinicopathologic features and survival outcomes in potentially resectable, locally advanced, and metastatic PDAC. Hazard ratio (HR) and 95% confidence interval (CI) were used as the pooled estimates. A total of 12 studies qualified for inclusion with 3751 PDAC patients. In resectable PDAC, the postoperative 5-year overall survival was significantly better in negative IPWC than in positive IPWC patients, with a pooled HR of 2.47 (95% CI, 1.90-3.21; P < 0.001; I = 69%) in a random-effects model. Likely, combined outcome showed a significantly longer survival benefit in the negative IPWC group (HR, 2.80; 95% CI, 1.94-4.04; P < 0.001) in terms of recurrence-free survival. The presence of positive IPWC did not significantly alter survival outcomes in those PDAC patients with locally advanced or metastatic disease. This systematic review and meta-analysis demonstrated that a positive IPWC status in patients with clinically resectable PDAC predicts a poor prognosis. Patients with positive IPWC should be regarded as a specific subgroup, with intensive adjuvant chemotherapy that seems to be warranted for further evaluation.