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Managing Cancer Care

Swelling, Edema, and Ascites

Cancer and its treatment may cause swelling which also can be called edema or ascites, depending on the area affected.

Swelling or edema

Swelling or edema is a build-up of fluid in the tissues. This can be caused by retaining salt and water because of certain medicines. It can also be a sign of heart, liver, or kidney damage or failure. Other causes might include surgery, infection, poor nutrition, tumor growth, or a blockage.

Swelling that happens because lymph nodes are blocked or removed causes lymph flow to be impaired. This is called lymphedema 

Some medications, like diuretics, can help edema.  Diuretics are often called water pills. They stimulate your kidneys to remove sodium and water from your body, so you'll urinate more often and get rid of extra fluid. But diuretics can have possible dangerous side effects. Talk to your doctor to learn more about this if you are prescribed diuretics for swelling or edema.


Ascites is excess fluid buildup in the belly (abdomen) because of pressure from tumors. It can make the belly hard and swollen (distended). Patients with ascites may also have nausea, vomiting, and fatigue. Sometimes the fluid also pushes on lungs which can cause difficulty breathing. Ascites is common in some cancers that have reached the advanced stages and spread in the abdominal area, including cancer of the ovary, liver, colon, stomach, or pancreas. Sometimes chemotherapy or surgery might help manage ascites.  More often, a procedure is done to drain the fluid, called a paracentesis. A paracentesis gives temporary relief that may last days or weeks, but fluid often comes back. Sometimes a catheter (tube) is placed and left in the belly, allowing fluid to drain out as needed. 

What to look for

  • Trouble breathing, especially when lying down
  • Heart racing or palpitations (or an awareness that the heartbeat is fast or irregular)
  • Feet and lower legs get larger (swell), usually when you sit in a chair, stand, or walk
  • Rings feel too tight for fingers
  • Hands feel tight when making a fist
  • Large, puffy, hard, or blown-up abdomen (belly)
  • Difficulty putting on pants or an outfit

What the patient can do

  • Limit your salt intake. Avoid using salt in cooking, and don’t eat foods that are very high in sodium (check food labels). Talk with your cancer team about this.
  • Eat as well as you can (see Eating Problems).
  • Take medicines as prescribed.
  • If your feet or legs are swollen, rest in bed with them up on 2 pillows.
  • When sitting up in a chair, keep your feet raised by sitting in a recliner or by placing your feet on a footstool with pillows.

What caregivers can do

  • Watch for any new symptoms, especially shortness of breath or swelling in the face.
  • Encourage the patient to keep the swollen body part propped up as high as is comfortable when sitting or lying down.
  • Learn to read food labels and talk with the cancer care team about how to keep intake of sodium down.
  • Don’t add salt, soy sauce, or monosodium glutamate when cooking or preparing food.
  • Weigh the patient every 1 to 2 days on the same scale, at the same time of day. Keep a list of weights and dates.

Call the cancer care team if the patient

  • Develops a hard, puffy, or blown-up belly
  • Notices that a swollen area is getting red or hot
  • Has shortness of breath or a racing heart
  • Can’t eat for a day or more
  • Hasn’t urinated or has passed very little urine for a day or more
  • Has only one arm or leg that swells up
  • Can press a finger into a swollen area and the dent remains after the finger is removed
  • Has swelling that spreads up legs or arms
  • Has a swollen face and neck, especially in the mornings
  • Gains several pounds in a week or less

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Gradalski, T.  A clinical note: Edema of advanced cancer: prevalence, etiology, and conservative management. A single hospice cross-sectional study.  Journal of Pain and Symptom Management. 2019;57(2):311-318. 

Gupta A, Sedhom R, Beg MS. Ascites or fluid in the belly, in patients with cancer. JAMA Oncology. 2019;doi:

Marinos P, Sarnowski A,  Moore A. The clinical management of abdominal ascites, spontaneous bacterial peritonitis and hepatorenal syndrome: are view of current guidelines and recommendations. European Journal of Gastroenterology & Hepatology. 2016;28(3):e10–e18.

National Comprehensive Cancer Network. Palliative Care. Version 2.2019. Accessed at on September 19, 2019.

Last Revised: November 30, 2021

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