February 9, 1998
Volume 50, No. 20
Researchers test more effective treatment for brain tumors
Emory cancer researchers are conducting clinical trials of a method of drug delivery that appears to increase dramatically the effects of traditional chemotherapeutic drugs on brain cancer.
Mark Gilbert, associate professor of neurology and co-director of the Brain Tumor Center at Winship Cancer Center, helped develop the principle of more prolonged drug exposure and is one of the primary investigators in this 30-site national trial.
Patients taking part in the study return to Emory Hospital within four weeks of surgery. They begin 72 hours of continuous chemotherapy, a process they will go through once a month for three months. After these intensive chemotherapy treatments are completed, the patients begin external radiation therapy.
"The problem with traditional chemotherapy, which is done on an outpatient basis, is that the drugs disperse in the bloodstream in about 15 minutes," Gilbert said. "An outpatient chemotherapy session lasts one to two hours. If it takes an hour for the drugs to make it to the brain, such a small amount of medication reaches the tumor site that it does not make much of an impact."
The blood-brain barrier, the lining of the brain that protects it from poisons in the bloodstream, tends to further diminish the amount of drug that makes it to the remaining cancer cells. With continuous chemotherapy, the drug has time to reach the brain, penetrate the blood-brain barrier and attack the cancer.
Previous trials of the protocol have shown great promise in patients with advanced brain tumors. This type of cancer includes glioblastoma multiforme, the most common and serious form of brain tumors in adults. These patients normally do not respond well to chemotherapy given over a short interval, and the average survival rate after diagnosis is less than a year.
Phase I and II trials of the drug protocol tested the safety and effectiveness of the drug. The current Emory study is a Phase III trial, conducted under the auspices of the Eastern Cooperative Oncology Group, which will compare the results of the protocol with the results of currently used methods.
"The outcomes from the Phase I and II trials were very encouraging," Gilbert said. "We have patients from those trials who are still doing well after seven years. The Phase III study has been underway for two years here at Emory, and preliminary results look as though the protocol is having a positive impact."
Currently more than 90 patients have taken part in the study, and researchers hope to enroll a total of 220 volunteers to complete their investigation. Participants must be newly diagnosed with a glioblastoma multiforme and must not have had radiation or any other kind of therapy. For more information on the trial, call Terri Armstrong, neuro-oncology nurse practitioner, at 404-778-2180.
Return to February 9, 1998 contents page