DEAR DR. GOTT: I am an 82-year-old lady and have been very active all of my life. Five months ago, I was diagnosed with a very rare form of cancer. I had a tumor on the outer side of my urethra. After several opinions, it was determined that I would have to have my bladder and urethra removed, as well as have a complete hysterectomy.

The operation was successful, but I now wear a urostomy pouch. My reason for writing is that, about a month ago, both of my feet started swelling. I saw my primary-care doctor, who told me that it was caused by the removal of lymph nodes during my surgery. I then called my surgeon, who agreed it was due to the lymph-node removal.

Is this a temporary situation or permanent? It is only affecting my left leg now. I am taking a diuretic and elevate my leg whenever possible. What else can I do?

DEAR READER: There are two circulatory systems within the body. The first and most well-known is the blood. This system carries red and white cells, platelets, plasma and nutrients throughout the body to sustain the muscles and organs.The second is the lymphatic. This system is vital to keeping the body healthy. It circulates protein-rich lymph fluid throughout the body, which collects waste products, bacteria and viruses. These substances are carried until they reach a lymph node, which then filters the fluid, removes the waste, and flushes it out of the body.When something causes the lymphatic system to back up, fluid builds up in the extremities. If a blockage occurs in the upper body, it may affect one or both arms, but most commonly affects one or both legs.There are some genetic causes of primary lymphedema; however, most cases are considered secondary, meaning they were caused by some other condition. Surgical removal of the lymph nodes, cancer, injury, infection and radiation treatments are the main causes of secondary lymphedema.In your case, the combination of your cancer and the removal of some of your lymph nodes likely caused your current problem.Unfortunately, there is no cure for lymphedema; however, there are ways of controlling the swelling and aiding drainage of the fluid. Compression of your leg will help by forcing the fluid up and out. This can be done with compression garments, bandages and pneumatic compression (a sleeve with attached pump that inflates and deflates, keeping the circulation moving). Light exercising of the affected limb or limbs is also important, since it may aid in lymph-fluid drainage. Finally, a special massage technique known as manual lymph drainage may be used. This procedure encourages the lymph fluid to drain out of the limb through a series of hand strokes.Wearing loose-fitting clothing and elevating the affected area may also be helpful. Physicians often prescribe diuretics, but they rarely do much good because the swelling is not due to fluid retention resulting from poor kidney function and may worsen the condition.Return to your primary-care physician to discuss your options and ask for his or her recommendations regarding which treatment might be appropriate. Perhaps you may benefit from using a combination of several methods.To learn more, I recommend you go online to the National Cancer Institute's Web site, www.cancer.gov, or to the Mayo Clinic at www.mayoclinic.com.