What causes abdominal distension and ascites in late-stage kidney cancer?

Abdominal distension and ascites in advanced renal cell carcinoma may be caused by multiple factors: 1. Hypoproteinemia: Patients with advanced renal cell carcinoma may develop hypoproteinemia due to inadequate protein intake or impaired protein synthesis, leading to decreased plasma colloid osmotic pressure, fluid extravasation into the peritoneal cavity, and subsequent ascites formation. 2. Renal insufficiency: Impaired kidney function reduces the effective elimination of excess fluid from the body, resulting in edema and ascites. 3. Liver metastasis: When renal cell carcinoma metastasizes to the liver, liver function becomes compromised, reducing protein synthesis. This further decreases plasma colloid osmotic pressure and contributes to ascites development. Additionally, in advanced stages of renal cell carcinoma, ascites may also result from other mechanisms, such as direct tumor compression of abdominal blood vessels or lymphatic vessels, which disrupts fluid circulation and lymphatic drainage, thereby promoting ascites accumulation.