The aim of this study was to review the current literature regarding prognostic outcome for patients with gastric cancer and positive cytology. We found that positive cytology was correlated with worse overall survival and higher recurrence rate among gastric cancer patients. However, the accuracy of peritoneal washing cytology (PWC) is found not to be optimal, which is a significant problem when using the modality in a clinical setting. Further studies with more sensitive methods are needed to establish the relevant role of PWC.