Clinical implications of peritoneal cytology in potentially resectable pancreatic cancer - Positive peritoneal cytology may not confer an adverse prognosis

Objectives: To determine the value of peritoneal washing cytology (CY) in determining resectability of pancreatic cancer. Summary Background Data: CY has been used widely in the diagnosis and staging of several cancers. However, its predictive value in identifying potentially resectable pancreatic cancer is undetermined. Methods: Peritoneal washing samples were collected from 233 patients with pancreatic cancer between June 1991 and August 2006. A total of 157 patients had resectable and 76 had unresectable lesions. Correlations between CY status and clinicopathologic parameters with overall survival rates were analyzed. Results: Malignant cells were identified in samples from 21 patients (13.4%) with resectable tumors and 27 patients (35.5%) with unresectable tumors. CY+ was more frequent in large tumors ( >= 2 cm) than small tumors (< 2 cm; P = 0.034). CY status did not correlate with any other clinicopathologic parameter. The overall survival of CY+ patients was worse than that of CY- patients (P = 0.047). Median survival following resection was 13.6 months for CY+ patients and 13.5 months for CY- patients. Among the patients who had unresectable lesions, median survival time was 5.9 months for CY+ and 6.1 months for CY- patients. However, among CY+ patients, those who underwent resection lived longer than those who did not (P = 0.019). Conclusions: Cytologic status has little predictive value for survival, and patients whose pancreatic cancer would other-wise be considered resectable should not be denied curative resection solely because they are CY+.