Does neoadjuvant treatment for gastric cancer patients with positive peritoneal cytology at staging laparoscopy improve survival?

Background: The purpose of this study was to identify clinicopathologic factors associated with positive peritoneal cytology (PPC) in patients with gastric cancer and to compare the overall survival (OS) of patients with PPC treated with and without neoadjuvant therapy. Methods: The medical records of 3,747 patients with gastric or gastroesophageal adenocarcinoma presenting to our institution (January 1995 to December 2005) were reviewed to identify those patients who underwent diagnostic laparoscopy as a staging procedure prior to consideration for neoadjuvant therapy. Associations between various clinicopathologic factors and OS were examined with Cox proportional hazards models. Kaplan-Meier curves were created to compare OS between groups. Results: Of 381 patients who underwent diagnostic laparoscopy for staging, 39 were found to have PPC without gross metastatic disease. Linitis plastica and tumors located at the gastroesophageal junction were identified as predictors of PPC (P < 0.01). Median follow-up for living patients was 51 months. Median OS for patients with PPC and no gross metastatic disease at laparoscopy (13 months) was no different from that for patients with gross metastatic disease at laparoscopy (10 months, P = 0.06). For the 39 patients with PPC and no gross metastatic disease, use of neoadjuvant therapy resulted in a 3-year OS rate of 12% versus 0% for patients who did not receive neoadjuvant therapy. Conclusion: Outcomes for patients with PPC without gross metastatic disease are not significantly different from those patients with gross metastatic disease at laparoscopy. However, some patients can achieve long-term survival and should be considered for neoadjuvant treatment prior to attempts at surgical resection.