Sometimes fluid can build up in the ankles and legs, which can cause swelling.
There can be several reasons for this, including being unable to move about as much as usual. Using a footstool to keep your feet up when sitting can help. It’s also helpful to gently exercise your legs while you’re sitting. A nurse or physiotherapist can show you some exercises to do. Water tablets (diuretics) may also be prescribed by your doctor to help reduce the swelling. In some situations, your doctor or nurse can supply pressure stockings to help the circulation in your legs.
If the swelling is only in one leg or ankle and is painful, red and hot, this may be a sign of a blood clot (thrombosis). People with cancer particularly have a higher risk of getting a blood clot and some cancer treatments can also increase your risk. Let your doctor know if you develop any of these symptoms, as treatment needs to be given as soon as possible.