Laser Thermal Therapy Extends Life In Glioblastoma Patients

A laser treatment that aims to destroy aggressive brain tumors can add an average of two months to a patient’s life, compared with chemotherapy, according to new research. The increase is small but meaningful for people who have only months left to live. Half of people with the brain cancer glioblastoma die within 14 months of diagnosis.

Even if initial treatment with surgery, radiation, and chemotherapy is successful, such brain tumors typically recur, leaving patients with few options. Currently, chemotherapy is the standard treatment for glioblastomas that recur.

“We’re not able to cure these types of really nefarious tumors, but we keep on working on finding new treatments that give people just a little more time. We’re nibbling away at this disease, step by step, and cumulatively these small advances can add up to a real improvement for patients,”

says senior author Eric Leuthardt, a professor of neurosurgery, neuroscience, biomedical engineering, and mechanical engineering & applied science at Washington University in St. Louis.

Recurring Tumors

The study gathers survival data by reviewing all laser treatments for glioblastoma from 2010 to 2016 at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine. In that time, 54 patients received 58 laser treatments. Of those, 17 treatments were performed on inoperable tumors and 41 on tumors that had recurred after primary treatment.

Most people diagnosed with glioblastoma undergo surgery that involves removing part of the skull to cut out the tumor, followed by both chemotherapy and radiation. But the tumor inevitably comes back, and a repeat operation is too taxing for many patients.

“By the time patients present with a recurrence, they’ve already endured open brain surgery, radiation, and chemotherapy,” Leuthardt says. “They are more fragile than they were the first time around, and their wounds may not tolerate reoperation well. It can take four to eight weeks to recover from brain surgery. It’s a lot to put them through again.”

In addition, some tumors are deep in the brain, which makes it impossible to remove them surgically without risking serious brain damage.

Laser Interstitial Thermal Therapy

Instead of surgery, doctors treat recurrent or inoperable tumors with chemotherapy or a heat therapy known as laser interstitial thermal therapy (LITT). Neurosurgeons drill a tiny hole in the skull and insert a laser, guiding it through the brain to the tumor on a path designed to cause the least damage. Once inside the tumor, the laser emits pulses of heat that kill the surrounding tumor cells.

The researchers found that patients with recurrent disease lived an average of 11.5 months after receiving laser therapy. Other studies have found that treatment with the chemotherapy drugs bevacizumab or temozolomide typically buys glioblastoma patients about nine months.

In addition, most people who received laser therapy were able to leave the hospital within a day or two.

“If you’ve only got four to nine months left, an extra two months matters,” Leuthardt says. “Having a therapy that people can tolerate relatively well so they can go home after the procedure, while adding a few months to their lives, means a lot to these patients.”

The Christopher Davidson Brain Tumor Research Fund supported the research; in addition, Leuthardt has a consulting relationship with Monteris Medical, the manufacturer of the laser ablation system used in this study.

Ashwin A Kamath, Daniel D Friedman, S Hassan A Akbari, Albert H Kim, Yu Tao, Jinqin Luo, Eric C Leuthardt
Glioblastoma Treated With Magnetic Resonance Imaging-Guided Laser Interstitial Thermal Therapy: Safety, Efficacy, and Outcomes
Neurosurgery, nyy375, https://doi.org/10.1093/neuros/nyy375

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