The most common causes of lower limb swelling, that is, swollen feet, in late stage of cancer patients are as follows: First, the patient has severe malnutrition or even cachexia, which will lead to hypoproteinemia, and at this time the colloid osmotic pressure of plasma is reduced, which will lead to swelling, and lower limb swelling is the most common situation. Secondly, the tumor compresses the blood vessels, such as the common iliac artery or the blood vessels around the groin, and the lymphatic vessels, causing the swelling of the feet in the lower limbs due to the obstruction of the blood vessels and lymphatic vessels. Thirdly, similar to swollen feet, there is thrombosis, for example, cancer patients are usually in a state of high coagulation, and this kind of venous thrombosis in the lower extremities will also lead to swollen feet on one side, which can be identified by a vascular ultrasound. Fourth, after advanced stage, the patient’s heart function, liver function and kidney function will degenerate, and when these functions fail, it will also lead to swelling of the limbs, of which swelling of the feet is also a part of the manifestation.