Survival and prognosticators of gastric cancer patients with only positive peritoneal lavage cytology.

16 Background: Treatment strategies for only positive peritoneal lavage cytology findings have not yet been established. The objective of this retrospective study was to clarify the survival and prognosticators in these patients. Methods: Overall survival (OS) rates were examined in 39 patients with gastric cancer who underwent a curative resection and had positive peritoneal cytology in the absence of overt peritoneal metastases between January 2000 and June 2015. Univariate and multivariate analyses were performed to identify risk factors using a Cox proportional hazards model. Results: A total of 39 patients were evaluated. The median overall survival was significantly longer in the 34 patients who received chemotherapy after surgery than that in the 5 who did not (19.1 vs 5.9 months, p < 0.01). Among the patients who received chemotherapy after surgery, univariate and multivariate analyses showed that pN3b was an independent significant prognosticator (hazard ratio of 4.169 with 95% CI: 1.108-15.684, p = 0.035). The median OS was 15.8 months when the patients diagnosed with N3b was 33.1 months when the patients diagnosed with N3a or lower. Conclusions: The prognosis of gastric carcinoma with positive peritoneal lavage cytology without peritoneal metastasis is still poor and need more aggressive treatment. The lymph node metastasis was a significant prognosticator in these patients.