Narrative review of malignant ascites: epidemiology, pathophysiology, assessment, and treatment.

Background and objective: Malignant ascites (MA) is common in patients with advanced cancer, and about 60% of patients with MA experience distressing symptoms. In addition, MA has been identified as a poor prognostic factor, therefore, making the management of MA an important issue. We aimed to review literature describing MA provide a narrative synthesis of relevant studies.

Methods: A literature search of articles published between 1971 and May 2023 was performed in PubMed, and Cochrane library using the words "ascites/malignant ascites" and the theme of each section. Authors independently selected the articles used and summarized. Finally, this manuscript was obtained consensus through discussed among all authors.

Key content and findings: The pathophysiological mechanism of ascites formation involves increased vascular permeability and impaired fluid drainage through the lymphatic system, which explain the occurrence of peritoneal carcinomatosis, portal hypertension due to liver tumors, liver cirrhosis in the background of hepatocellular carcinoma, and Budd-Chiari syndrome caused by tumor occlusion of the hepatic vein. The efficacy and safety of various treatments and procedures have been investigated previously; however, no treatment guidelines have been established yet. Diuretics and paracentesis are often selected as the first lines of treatment. Intraperitoneal drug administration (catumaxomab, bevacizumab, aflibercept, hyperthermic intraperitoneal chemotherapy, triamcinolone), indwelling peritoneal catheters, peritoneovenous shunting, and cell-free and concentrated ascites reinfusion therapy are commonly used to manage refractory ascites. A new device for this purpose is alfapump, which transfers ascites fluid from the peritoneum into the urinary bladder. In addition, thoracic epidural analgesia may be effective for managing ascites-related symptoms.

Conclusions: Despite these options, no standard treatment for MA has been established yet because few trials have been conducted in this area. There are many issues to be investigated, and future research and treatment development are expected.