U researchers get smart with tumors

Sean Madigan

Researchers at the University’s Department of Neurosurgery are beginning trials on a treatment for reoccurring brain tumors more than 50,000 times stronger than chemotherapy.
Dr. Walter Hall, associate professor of neurosurgery at the University and leader of one of nine teams in a nationwide study, recently received clearance from the Institutional Review Board to begin the first phase of their trials to combat glioblastoma multiforme, a specific type of brain tumor.
Each year, more than 17,500 people in the United States are diagnosed with cancerous brain tumors. For every 100,000 people in Hennepin and Ramsey counties, doctors found brain tumors in an average of 7.4 men and 4.8 women between 1992 and 1996. Glioblastoma multiforme accounts for approximately 35 percent of all brain tumors.
The treatment begins by inserting a catheter through the brain directly into the tumor.
The therapy links an extremely potent toxin, Interleukin 4-toxin — a form of bacteria — to a harmless carrier molecule.
Dubbed the “smart bomb,” the treatment seeks out and binds only to tumor cells. It kills the tumor cells without affecting the healthy cells surrounding it.
The catheter releases the IL4-toxin over an extremely low flow rate for four days. Gradually, a wave of fluid surrounds the tumor and binds to the cells.
Once the poison binds to the tumor cells, the tumor should be killed in less than six hours. With the exception of an initial biopsy, the patient is conscious during the entire procedure.
The procedure lasts for four days.
“If it works it could be potentially curative,” Hall said.
Currently, doctors treat brain tumor patients by removing the tumor then administering radiation and chemotherapy, but after this entire process, Hall said patients are expected to live for little more than a year.
“This therapy is for people who go through all that and the tumor grows back,” Hall said.
To date, just one patient has undergone treatment, which took place in Charlotte, N.C.
Hall hopes trials at the University will begin soon, possibly as early as Tuesday or Wednesday.
While in the first phase of the trials, Hall and other researchers are testing safe dosage levels.
“You have to make sure you don’t cure the tumor and kill the patient,” Hall said. Researchers will not test the smart bomb’s degree of effectiveness until the second phase. But Hall said seeing results will take time.
“You kind of get an idea of the way things are going as you are doing it,” Hall said.
On average, tumors range in size between one-fifteenth and one-thirtieth of the brain, about the size of a small egg. But Hall said tumors can reach a size of more than half of the brain.
“Oftentimes tumors grow in areas where there is not a lot of function,” Hall said. “Like the brain’s frontal lobe — you could hide a baseball in there and you would never find it.”
The procedure is budgeted for trials on 30 people nationwide, with four to take place at the University.