University clinical trials test new ways to fight brain cancer

New clinical trials are being conducted to find better ways to address glioblastoma

by Michelle Griffith

In 2015, engineer Brian Braun endured an invasive brain cancer surgery that required a three-week recovery in intensive care. When his tumors came back in 2018, he thought he would have to undergo the harsh procedure once again. 

However, cutting-edge clinical trials at the University of Minnesota allowed him to undergo a less taxing laser treatment with a shorter recovery time instead. After the new surgery, Braun was back to work in two weeks.

The laser treatment is part of a series of clinical trials being held by the Department of Neurosurgery to treat glioblastoma— an aggressive brain cancer. The trials include laser treatment, engineered viruses and a drug that helps identify where tumors are located.

“These advances are kind of space-age. If I were to tell you, ‘I’m gonna inject a virus into your brain,’ it’s pretty weird right?,” said Dr. Clark Chen neurosurgeon and chair of the Department of Neurosurgery. 

The brain is surrounded by a protective barrier that shields it from toxins but also prevents many treatments, such as chemotherapy, from reaching the brain, Chen said. The methods used in the University’s clinical trials are designed to reach the cancer cells directly, ensuring the most success, he said. 

One of the treatments the University is testing is called laser ablation, which uses a laser to heat and kill the cancer cells.  This process is not as invasive as other brain surgeries and uses a magnetic resonance imaging machine and laser to erode the tumor, Chen said.

Braun said his laser ablation experience was positive.

“It has been just a tremendous recovery compared to more invasive brain surgeries,” he said, adding he had an increased appetite and more energy. 

The University is also exploring the use of viruses to combat brain cancer. In one method, a virus engineered to combat glioblastoma called Tocagen is injected into a patient’s brain after the majority of the tumor is removed in surgery. The patient then takes a drug that only affects parts of the body where the virus is located. The trial is in its final stages, and Chen hopes to have results in the coming years.

Another treatment uses a person’s immune system to ensure the tumor doesn’t reappear after surgery. Like the other virus method, a patient undergoes surgery, has the bulk of the tumor removed and is exposed to the virus. The patient also takes a drug that kills the virus and reacts with the immune system to stop the growth of future cancer cells. Clinical trials for this method will begin in the fall. 

In a few months, another University clinical trial will test a drug called 5-ALA, which allows surgeons to identify a tumor’s location using special lighting. It is often difficult to discern tumor from brain matter when looking at the brain, Chen said.  

Glioblastoma is the most common form of brain cancer that creates tumors and will affect an estimated 24,000 people in 2018, of which about 17,000 will die, according to the National Cancer Institute. 

“This tumor is so aggressive that it basically eats up the brain,” Chen said. “This disease is so devastating because it fundamentally erodes what we consider to be human.” 

If glioblastoma is left untreated, most people die within three months. If chemotherapy is unsuccessful, then a person is expected to live four to nine months, Chen said.