Lymphedema—the medical term for swelling caused by the buildup of fluid (lymph) in the soft tissues—develops because of some blockage of the lymphatic system . Most lymphedema in cancer patients results from scarring after the surgical removal of lymph nodes or after radiation therapy . It usually involves areas next to large collections of lymph nodes in the armpit (axilla), pelvic region and inguinal (groin) areas. The lymphatics are obstructed and swelling in the arms or legs is the result.
    In its early phase, the swelling of the limb will "pit" with finger pressure. Elevating the arm or leg or using an elastic support arm glove or stocking will help reduce the swelling and improve the lymphatic flow.

Acute and Chronic Lymphedema  Acute lymphedema may be a temporary condition. It can happen after a radical surgical procedure with lymph node dissection or after an acute inflammation such as an infection in the limb. More often seen in cancer patients is chronic lymphedema. Sometimes it results in only minor swelling and discomfort. But occasionally it can lead to grave disability and disfigurement.
    Chronic lymphedema is more difficult to reverse than the acute variety because the more the limb swells the harder it is to drain the fluid adequately. People with chronic lymphedema are also more susceptible to infections or local injuries, which results in more scarring and additional lymphedema. Infections of the limb—known as cellulitis—often develop after even minor cuts or abrasions and they can often only be controlled with long-term antibiotics.