Radiation May Prevent Failure Of Hemodialysis
Columbia Presbyterian Center the Only Institution in U.S. Testing Procedure that May Save Thousands of Lives
NEW YORK, June 29, 1999 A new treatment that prevents the formation of blockages in blood vessels critical to kidney dialysis is now being evaluated in clinical trials at the Columbia Presbyterian Center of New York Presbyterian Hospital in New York City. In the treatment, radiation is delivered with external electron beams to blood vessels that may otherwise narrow as the result of the hemodialysis procedure, eventually limiting or stopping the flow of blood through those veins. Columbia Presbyterian Center received formal approval to begin the trials from the Food and Drug Administration (FDA) late last year, and is the only institution in the United States currently testing this procedure as a prophylactic treatment, before narrowing occurs.
Thousands of Hemodialysis Patients, One Billion Dollars Per Year
"The difficulty in maintaining functional blood vessel grafts for hemodialysis in people with kidney failure is a serious problem, so I am delighted that this research is being done," said Dr. Joel D. Kopple, president of the National Kidney Foundation. According to the National Kidney Foundation (NKF), more than 200,000 patients receive hemodialysis treatment annually in the U.S., typically delivered via veins in the arm or leg. About 80 percent of these patients, or roughly 160,000 people, receive treatment via a synthetic graft, which permits a "high flow" system necessary for dialysis. Of these 160,000, approximately 50 percent, or 80,000, fail within two years. Of these, up to one-half fail because of stenosis, the closing up of blood vessels, as a result of the high flow system. The complications are costly - according to the NKF, maintenance and care of vascular access sites for kidney patients cost American taxpayers about $1,000,000,000 per year.
Preventing Tissue Growth to Eliminate Blockages
"Hemodialysis changes the flow of blood in the patient's affected veins, which causes a narrowing as the tissue grows in the muscle wall of those veins," says Dr. Peter B. Schiff, professor and chairman, Department of Radiation Oncology, Columbia University College of Physicians & Surgeons, and director, Radiation Oncology Service, Columbia Presbyterian Center of New York Presbyterian Hospital. "Problems typically occur at the end of the tubing, or shunts, used in hemodialysis. We contend that radiation delivered at that site before dialysis is given may very well prevent the growth of that tissue, therefore eliminating blockages as a hazard of the kidney treatment."
According to Dr. Schiff, many hemodialysis patients ultimately suffer illness or even death each year when access to blood vessels is eliminated from developing stenosis. "The knowledge we've gained from using radiation to treat cancer patients may apply well to kidney patients," says Dr. Schiff. "Ultimately, if our theory proves right, then thousands of kidney patients will benefit each year. Not only will lives be saved and extended, but the quality of those lives will improve and the cost of medical care will be significantly reduced as the need for repeated surgical procedures to insert new shunts is eliminated in many cases."
"The placement of these grafts and the surgical or other interventions that are often necessary to maintain the function of these grafts are major causes of suffering, hospitalization and inadequate hemodialysis treatments," said Dr. Kopple of the NKF. "If radiation turns out to be beneficial for the blood vessel grafts, it will benefit kidney failure patients throughout the world. I look forward to the results of this study."
Dialysis is the process of maintaining the chemical and fluid balance of the blood when kidneys have failed. Hemodialysis is a type of dialysis that involves the use of an artificial kidney machine to filter waste products and excess fluid from the bloodstream. When vessels develop stenosis, new sites must be found to conduct dialysis, resulting in additional surgeries. Dialysis patients whose veins develop stenosis typically experience the narrowing after about 1.5 years of treatment.
Painless Procedure, Minimal Risk
Patients in the trial will receive one or two external radiation treatments (approximately 15 minutes per treatment) one month after surgery is performed to insert the tubing used in hemodialysis. The delivery of the radiation is painless. According to the leader of this study, Dr. Ronald D. Ennis, associate professor of Clinical Radiation Oncology, Columbia University College of Physicians & Surgeons, and associate attending physician, Radiation Oncology Service, Columbia Presbyterian Center, the radiation portion of this treatment carries minimal risk. "Each dose used in this trial delivers about 800 units of radiation, a relatively low dose and less than what a patient might receive for treating a tumor in the leg or arm," said Dr. Ennis. "The radiation is limited to the very small area of affected tissue, so this procedure is expected to be very safe."
Columbia Presbyterian Center's trial is a Phase I safety study and will include 30 patients over the next six months. Fifteen patients will receive one dose of radiation and 15 will receive two doses. Once this phase of the study is completed, Columbia Presbyterian Center will conduct a randomized trial with hundreds of patients to establish the procedure's effectiveness, pending FDA approval.
With more than 40,000 square feet of clinical and basic science research space, the Department of Radiation Oncology at Columbia Presbyterian Center of New York Presbyterian Hospital is the largest facility of its kind in the New York metropolitan region. The department has eight board certified radiation oncologists and a staff of more than 100 people at its two Manhattan-based locations. For more information, visit the Radiation Oncology department's web site or call 212-305-8096.
For more information about the hemodialysis study or to inquire about candidacy for inclusion in the trial, contact the Department of Radiation Oncology at Columbia Presbyterian Center at 212-305-7997.
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