BackgroundThe management of malignant ascites is critical for treating patients with advanced pancreatic cancer. The purpose of this study was to assess the safety of cell-free and concentrated ascites reinfusion therapy (CART) and its impact on the prognosis of patients with advanced pancreatic cancer who have massive malignant ascites. MethodsThis study analyzed 47 procedures in 29 patients who underwent CART for ascites caused by pancreatic cancer between 2015 and 2022. Among them, 7 patients who received chemotherapy following CART were classified as the chemotherapy group, while 22 patients without chemotherapy after CART were classified as the palliative care group. ResultsAmong the 47 procedures, adverse events (AEs) were observed in 9 procedures (19 %). Grade 2 adverse events were observed only in one procedure, manifested as fever. There were no grade 3 or 4 AEs, nor were there any treatment-related deaths. The median survival time was 4.0 months in the chemotherapy group and 0.7 months in the palliative care group (p = 0.004). The albumin level in the chemotherapy group was significantly higher than that in the palliative care group. ConclusionCART is feasible and might be the optimal option to enable prolonged use of chemotherapy to improve the prognosis for late-stage pancreatic cancer patients.