In a novel research study to begin this week at the Abramson Cancer Center of the University of Pennsylvania, Kathryn Schmitz, PhD, MPH, Assistant Professor in Epidemiology, will help to determine the extent to which a slowly progressive program of strength-training exercises is safe for breast cancer survivors with and without symptoms of lymphedema.
Lymphedema, which is characterized by a painful swelling of an affected arm and resulting loss of arm function, is one of the most common and feared side effects of breast-cancer treatments that involve lymph-node removal and/or radiation therapy.
Actions of the lymph system include regulating the balance of fluids in the limbs and fighting infections. When lymph nodes in the armpit are removed or damaged, patients can no longer appropriately regulate the fluid in their affected arm - which leads to swelling that can range from mild to extensive (bordering on elephantitis) and quite disfiguring. "Statistically, this is a public health problem," says Schmitz. "It affects up to one-half of the nearly two million breast-cancer survivors alive in the U.S. today - which means that there may be as many as one million women suffer from some form of lymphedema."
"Further, the psychological effects are enormous," adds Schmitz. "Indeed, many women have reported that they would rather have another mastectomy than lymphedema - because it's a painful, constant, and debilitating reminder of their breast cancer."
Current clinical guidelines advise lymphedema sufferers to not participate in any vigorous upper-body exercise; and, in particular, to not lift objects that weigh more than five to 15 pounds. "A gallon of milk weighs eight pounds," notes Schmitz, "so, basically, you're telling women, 'Don't carry your own groceries … don't pick-up your own grandchildren … don't live your own lives!' And the guidelines are based on air … on nothing. There's no scientific evidence to suggest that they're correct."
Strength training, believes Schmitz (an exercise physiologist), is an intriguing intervention for breast-cancer survivors as there is evidence that exercise improves health parameters and quality of life. Based on data from her own previous study (as well as other reports in the medical literature), a program of slowly-progressive weight-lifting exercises permits women to gradually increase the physical capacity of the damaged arm in a controlled setting, making it less likely that the occasional activities of daily living that require strenuous upper-body work - such as shoveling snow or carrying children - would over-stress the injured lymphatic system.