A New Way to Detect Lymphedema
(Ivanhoe Newswire) – A painful condition that affects close to 10 million people in the United States might finally be detectable and treatable.
Researchers have identified a set of proteins that show the presence of lymphedema. Lymphedema is an inflammatory condition that results from the tissues throughout the body. It is a condition that can arise as a consequence of radiation therapy. Study author Stanley Rockson, MD, professor of cardiovascular medicine at Stanford University, was quoted as saying, “about one in four breast-cancer survivors eventually develop lymphedema.” In underdeveloped countries, it could arise as a consequence from parasite infections.
Lymphedema can halt normal immune-cell flow that results in the buildup of fluid in the affected area of the body. Also it can result in thickening of the skin, distinct inflammation, accumulation of fibrous tissue, a marked expansion of the fatty layer underneath the skin, and excessive blood-vessel formation.
“By the time the main symptom — swelling of one or more limbs — is detectable, the condition may have gotten such a foothold that it becomes difficult or impossible to reverse, at least given current treatment options,” Rockson said.
So far physical inspection is the only way to diagnose lymphedema and it is usually overlooked or misdiagnosed. However, the biological events could be present five years or more before symptoms are noticeable.
There are no effective drugs for fighting lymphedema, only expensive time-consuming physical therapy. Physical therapy can reduce swelling and progression, the condition remains a long-term problem. Rockson said, “Lymphedema virtually never just goes away on its own.”
As a result from the effects of the condition on the body, patients experience social withdrawal, body-image deterioration, and other quality of life issues. "This is especially ironic in the case of cancer survivors who have endured difficult life-saving interventions, only to find that now cured, they're unable to enjoy their lives," Rockson explained.
For the study, Rockson’s team obtained skin-biopsy samples from lymphedematous and normal tissue of 27 patients. They used molecular methods to determine that the overproduced protein themselves are already known for circulating in the bloodstream of all people and already have a fast commercial blood test.
Statistical models tested six proteins’ levels in the participants’ blood and were able to distinguish who had lymphedema. The six proteins together, at certain levels and ratios, appeared to serve as a biomarker for lymphedema. "These biomarkers may themselves lead us to valuable pharmaceutical targets," Rockson said.
Rockson’s team collected blood from 36 different lyphedematous and 15 healthy adults. They then tested them on the panel. The test had a 90% accuracy rate for distinguishing lymphedema from healthy people.
Levels of the proteins begin to climb early in the onset of the condition. This test could determine the risk for lymphedema before symptoms occur, allowing doctors to suggest appropriate therapy earlier to spare patients the painful, damaging effects the disease can inflict.
"In addition, a standardized, accurate bioassay for lymphedema could help to pave the road for future human clinical trials of drugs to treat it,” Rockson concluded. Rockson hopes to use the new test in clinical trials of pharmaceutical agents for lymphedema.
SOURCE: PLoS ONE, December 2012