Peritoneal Washing Cytology: Prognostic Value of Positive Findings in Patients with Gastric Carcinoma Undergoing a Potentially Curative Resection

Background And Objectives: Free cancer cells in the abdominal cavity exfoliated from a tumor are considered to be responsible for peritoneal dissemination, the most frequent pattern of failure in gastric carcinoma patients treated with curative surgery.

Methods: A prospective survival analysis was performed with 91 gastric carcinoma patients treated by potentially curative resection. Cytology was performed for all the patients. The method of Kaplan and Meier was used to construct curves with diagnosis of peritoneal dissemination and cancer death as the end points. Multivariate analysis by Cox's proportional hazards model was performed to identify independent prognostic factors of significance.

Results: Patients with a positive cytology result were confirmed to have a greater risk for recurrence in the pattern of peritoneal carcinomatosis and hence a significantly inferior prognosis. Positive cytology was the only significant independent prognostic factor among the curatively resected patients with advanced gastric carcinoma.

Conclusions: Peritoneal lavage cytology should be employed for all advanced cancer undergoing potentially curative resection for added accuracy in the stage classification. The results should also reflect the eligibility of the patients for future clinical trials involving perioperative intraperitoneal chemotherapy.