Association of ascitic neutrophil to lymphocyte ratio with prognosis in patients with advanced gastric cancer

Abstract

443 Background: Approximately 40% of metastatic gastric cancer patients develop peritoneal carcinomatosis, and this condition leads patients to grave prognosis. Blood neutrophil to lymphocyte ratio (NLR) is associated with prognosis in various solid tumors, such as non-small cell lung cancer, colorectal cancer, and gastric cancer. We performed this study to investigate the prognostic significance of NLR of ascitic fluid. Methods: This is retrospective study. Patients were consecutive included if they; 1) had histologically confirmed gastric adenocarcinoma, poorly cohesive carcinoma, or poorly differentiated carcinoma, 2) were relapsed after curative resection or initially metastatic, 3) had ascites due to peritoneal metastases of gastric cancer, 4) had received paracentesis at least once and the result of ascites exam is available. Patients with clinically active infection in the time of paracentesis is excluded. If multiple times of paracentesis was done, we used initial result. Results: From March 2012 to August 2018, total 157 patients who were visited in Pusan National University Yangsan Hospital met the inclusion criteria. Median age is 58 (29-86) years and male patients was 63% (n = 99). In 38.9% (n = 61) patients, gastric cancer was diagnosed in primary site and in ascites synchronously. At the time of first paracentesis, 47.1% (n = 74) of patients had already been received palliative chemotherapy due to metastatic gastric cancer. In the ascites, mean and median NLR is 2.2±6.8 and 0.3 (0-65). All except 3 patients were expired, and the median survival time form paracentesis was 47 (95% confidence interval 38.6-55.4) days. In the Kaplan-Meier survival analysis, patients with higher NLR (≥0.33) have shorter survival from paracentesis (39 days, 95% CI 32.5-45.4) in compared to lower NLR ( < 0.33) (61 days, 95% CI 29.4-92.6, log-rank p = 0.011). In the additional analyses, higher neutrophil count (41 vs 72 days, p = 0.045) and lower protein level (32 vs 61 days, p = 0.018) of ascites are also poor prognostic factor. Conclusions: High NLR of malignant ascites is poor prognostic factor in patients with gastric cancer. The role of neutrophil in the malignant ascites should be tested in a new perspective.