Should Positive Cytology Revealed by Intraoperative Lavage Preclude Radical Resection in Resectable Pancreatic Cancer?

The aims of this review were to determine whether positive peritoneal lavage cytology (CY+) precludes radical resection in pancreatic cancer and to propose prospections for future studies.MEDLINE, Embase, and Cochrane Central were searched for related articles. Dichotomous variables and survival outcomes were analyzed with the estimation of odds ratio and hazards ratio (HR), respectively.A total of 4905 patients were included, of which 7.8% were CY+. Positive peritoneal lavage cytology was correlated with poor overall survival (univariate survival analysis [HR, 2.35; P < 0.00001]; multivariate analysis [HR, 1.62; P < 0.00001]), poor recurrence-free survival (univariate survival analysis [HR, 2.50; P < 0.00001]; multivariate analysis [HR, 1.84; P < 0.00001]), and higher initial peritoneal recurrence rate (odds ratio, 5.49; P < 0.00001).Although CY+ predicts poor prognosis and a higher risk of peritoneal metastasis after curative resection, it is not sufficient to preclude curative resection based on the current evidence, and high-quality trials should be conducted to assess the prognostic impact of operation among resectable CY+ patients. In addition, more sensitive and accurate methods to detect peritoneal exfoliated tumor cells and more effective comprehensive treatment for resectable CY+ pancreatic cancer patients are clearly warranted.