New treatment found to aid chemo

Todd Milbourn

By determining that a treatment that opens a window in the brain improves chemotherapy response, University neurosurgeon Dr. Walter Hall has helped open a window of hope for thousands who suffer from brain tumors.
In a study led by Hall and conducted across six universities worldwide, a team of researchers have found patient response to chemotherapy can be significantly increased using a technique developed 21 years ago known as blood-brain barrier disruption.
The treatment offers new hope and promise for patients suffering from malignant brain tumors.
Chemotherapy, or chemical therapy, is a treatment used in tandem with surgery and radiation therapy to battle cancerous brain tumors. During treatment sessions, medication is delivered intravenously to the patient. However, a significant amount fails to reach the brain where it is needed. It’s blocked by a protective wall around the brain known as the blood-brain barrier.
“It’s there for our protection,” Hall said. “But the problem is, if you’ve got an infection and can’t get antibiotics in there, it becomes a detriment to the patient.”
Dr. Edward Neuwelt, a University of Oregon neurosurgeon, pioneered a clinical application to disrupt the blood-brain barrier in 1978.
The study conducted by Hall’s team, initiated in June 1996, elaborated on Neuwelt’s work and determined blood-brain barrier disruption is a safe and effective way to treat brain tumors.
The study showed 80 percent of patients who suffer from the most common brain tumor, glioblastoma multiforme, responded to blood-brain barrier-enhanced chemotherapy.
Using traditional chemotherapy, only 30 percent of patients responded to treatment.
Researchers studied 221 adult patients who underwent 2,464 procedures over three years.
The procedure is done under general anesthesia. Once a patient is sedated, a catheter delivers Mannitol, a sugar-saturated blood-brain disrupter, through an artery directly to the brain. The Mannitol draws fluid out of the blocked blood vessel and essentially opens a “window” in the barrier.
Once the “window” is opened, surgeons have thirty minutes to deliver the chemotherapy directly to the brain.
Patients receive one course of chemotherapy with blood-brain barrier disruption once a month for a year.
Following treatment sessions, patients suffer from side effects similar to those felt after traditional chemotherapy, such as hair loss, reduced sperm count and menstrual changes. However, because the treatment is done under anesthesia, few feel nauseated after the procedure, and most patients are out of the hospital within 24 hours.
“If we do the procedure in the morning, many are eating by dinner time,” Hall said.
The study revealed there is a slight risk of brain swelling, or cerebral edema, and stroke with the procedure, Hall said.
To receive the treatment, patients must be in otherwise good health and strong enough to withstand 24 treatments in a one-year period.
Although the new procedure holds much promise, Hall envisions further advancements in the near future.
“We’re aggressively pursuing an anti-cancer vaccine and a targeted toxin,” said Hall of emerging treatments being developed at the University.
“Newer treatments on the horizon better than blood-brain barrier disruption will hopefully be available within a year,” Hall said. “And that’s what keeps me in this.”

Todd Milbourn covers science and technology. He welcomes comments at [email protected]