Prognosis of gastric adenocarcinoma patients with various burdens of peritoneal metastases

Background Peritoneal metastases (PM) in patients with gastric adenocarcinoma (GAC) may be identified by diagnostic laparoscopy (DL) or imaging (I). Although prognosis is poor, some patients have excellent outcome. We compared the overall survival (OS) of patients in 3 groups: those with positive cytology (CY+) by DL (DL-CY+), those with gross PM (GPM) by DL (DL-GPM+) and with GPM obvious on I (I-GPM+). Methods 146 GAC patients were identified. The Kaplan-Meier analysis, univariate, and multivariate Cox proportional hazards regression models were employed. Results Patients were primarily men (67%), with good ECOG scores (0-1; 89%), had DL (84%), had poorly differentiated GAC (92%), and had received chemotherapy (89%). The median OS for all patients was 15 months (5%CI, 12.9-18.2 months). The DL-CY+ group had median OS of 22.5 months (95%CI, 15-29.3 months). Patients with I-GPM+ had four times the risk of death than those with DL-CY+ (P < 0.001) and patients with DL-GPM+ had two times the risk of death than those with DL-CY+ (P = 0.001). At 36 months, all DL-GPM+ and I-GPM+ had died but 8 patients with DL-CY+ remained alive. Conclusions Some GAC patients with DL-CY+ have long OS; therefore, novel strategies to further prolong their OS are needed.