Scientists Investigating Genetic Cause Of Lymphedema (dateline July 7, 2000)
Lymphedema, the chronic swelling of the arms or legs from an accumulation of lymphatic fluid, is a painful condition that can worsen without treatment. Hereditary lymphedema can occur spontaneously while secondary lymphedema sometimes occurs after cancer treatments, especially if some of the lymph nodes are surgically removed. Lymphedema is a side effect of axillary node dissection (removal of the underarm lymph nodes), a common procedure for breast cancer patients.
For years, researchers did not know why some individuals developed lymphedema (either sporadically or as a side effect of disease treatment) while others did not. Recently, researchers from the University of Pittsburgh have identified human genetic errors that can account for hereditary lymphedema. According to the researchers, these findings may help individuals suffering from either hereditary or secondary lymphedema.
The researchers have discovered that mutations of a gene responsible for the growth of lymph vessels that drain tissues of excessive fluid may cause hereditary lymphedema. Some individuals produce abnormal forms of the gene, called vascular endothelial growth factor receptor (VEGFR3), which can cause irregular development of the lymphatic system. According to the researchers, if a cancer patient has a mutation of the VEGFR3 gene, she may be more likely to develop lymphedema as a side effect to lymph node surgery.
Up to 10% of women who have mastectomy (breast removal) and lymph node removal may develop lymphedema of the arm. According to Robert Ferrell, PhD, professor of human genetics at the University of Pittsburgh’s Graduate School of Public Health, this research may help physicians identify women at risk of lymphedema before surgery and anticipate and address problems before they become severe.
“Our work is the first to identify a genetic mutation responsible for lymphedema,” said researcher David Finegold, MD, in a press release. This research helps scientists understand a biological reason for why lymphedema occurs, said Dr. Finegold. The researchers believe that other genes may also be involved in the development of lymphedema. Additional research will be conducted to further investigate the genetic factors involved.
Lymphedema is a painful condition for those who suffer from it. The treatment of lymphedema varies, but usually includes:
- massage therapy to stimulate the movement of lymph (fluid circulating through the lymphatic system) to healthy lymph vessels
- wrapping the affected limb with low stretch bandages to increase drainage and prevent fluid from refilling the limb
- stretches and exercises, as instructed by health care providers
and using compression garments after swelling has been reduced.
- The June 28, 2000 University of Pittsburgh Medical Center press release, “Genetic Cause of Lymphedema Discovered by University of Pittsburgh Researchers Reported in Nature Genetics,” is available at http://www.eurekalert.org/releases/upmc-gco062800.asp
- An abstract of the study discussed in this article is
available from Medline at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed
- A report of the study discussed in this article appears in the June 2000 issue of Nature Genetics ( http://www.nature.com/ng/)
- To learn more about lymphedema, including prevention and treatment of the condition and how to contact national lymphedema organizations for additional information or support, please visit http://www.imaginis.com/breasthealth/lymphedema.asp
- To learn more about lymph nodes and the lymphatic system, please visit http://www.imaginis.com/breasthealth/lymph_nodes.asp