Why does malignant ascites cause abdominal swelling?

Cancer can irritate the lining of the abdomen, block lymphatic drainage or affect blood flow through the liver. These changes can shift the balance between fluid entering and leaving the abdominal space. As fluid collects, it presses on the stomach, bowel, diaphragm and nearby organs.

That pressure may cause a tight or heavy feeling, early fullness after eating, breathlessness when lying down, nausea, constipation or discomfort. The abdomen may enlarge gradually or become tense over a shorter period. Other causes of swelling exist, so examination is needed to understand the fluid and its cause.

Tell your oncology or medical team about increasing abdominal size, reduced appetite, new discomfort or changes in breathing. They may examine your abdomen and use imaging to look for fluid. A sample of the fluid can sometimes help clarify its features and guide care.

Treatment is tailored to your symptoms and overall plan. Options may include medicines, treatment directed at the cancer, or drainage of fluid when pressure is troublesome. Do not start a restrictive diet or fluid plan without medical guidance, particularly if you have kidney, heart or liver problems.

Seek urgent help for severe or sudden abdominal pain, repeated vomiting, inability to pass stool or gas, new confusion, fainting, fever, or rapidly worsening breathlessness. A tight abdomen with difficulty breathing deserves prompt assessment.

What is causing the fluid in my abdomen? How will you monitor it? Could drainage or medicine relieve the pressure? Which changes should lead me to contact the team urgently?