Innovative Laser Procedure Offers New Hope for Recurrent Brain Tumors

Published: February 26, 2026

High-grade astrocytoma, including glioblastoma, is a fast-growing brain cancer that often returns even after surgery. Patients with recurrent tumors typically survive only four to five months.

The Challenge with Immunotherapy

Immune checkpoint inhibitors are drugs that help the body’s own immune system, especially cancer-fighting T-cells, detect and attack tumor cells. While these drugs can prevent cancer recurrence in many parts of the body, they are usually not effective in the brain.

The reason is the blood-brain barrier — a tightly sealed layer of cells that protects the brain by preventing many substances, including immune cells, from entering. This barrier makes it very difficult for T-cells to reach the tumor.

A New Approach Using Lasers

Researchers at Keck Medicine of USC may have found a way to temporarily open this barrier, allowing immune checkpoint inhibitors like pembrolizumab to work effectively.

This approach uses Laser Interstitial Thermal Therapy (LITT). LITT applies heat to destroy tumor tissue while temporarily disrupting the blood-brain barrier.

Clinical Trial Results

In a Phase 1/2b clinical trial, patients treated with LITT followed by pembrolizumab showed remarkable outcomes:

• Nearly half of the patients were still alive at 18 months.
• Patients who received standard surgery followed by pembrolizumab did not survive to 18 months.
• Over one-third of patients lived more than three years, far exceeding the typical survival of four to five months.

Why This Matters

These results suggest that LITT can make immune checkpoint therapy more effective against aggressive brain tumors. For patients with advanced cancer and limited treatment options, this method offers real hope for extended survival.

Dr. David Tran, MD, PhD, chief of neuro-oncology at Keck Medicine and lead author of the study, stated:

“This approach could significantly improve patients’ lives and offer new hope for their families.”

How LITT Works

Previous research by Tran and colleagues showed that the heat from LITT temporarily disrupts the blood-brain barrier for several weeks. This window allows T-cells, activated by the immune checkpoint inhibitor, to reach and target the cancer cells.

Brain Tumor: Symptoms, Risk Factors, and Preventive Care

Early Warning Signs of Brain Tumors

Recognizing early symptoms can save lives. Seek medical attention promptly if you or a loved one experience:

• Persistent headaches not relieved by over-the-counter painkillers
• Sudden changes in vision or hearing
• Nausea or vomiting without an obvious cause
• Weakness or numbness in any part of the body
• Unusual fatigue or sleep disturbances
• Memory lapses or difficulty concentrating

Early detection allows for timely diagnosis and better treatment outcomes.

Risk Factors and High-Risk Groups

Certain individuals are at higher risk for developing brain tumors:

• Family History: A history of brain tumors or genetic syndromes in the family
• Genetic Syndromes: Conditions like Li-Fraumeni Syndrome or Neurofibromatosis
• Environmental Exposures: Radiation, chemicals, or high pollution levels
• Age and Gender: Some tumors are more common in children or older adults
• Prior Head Injury or Surgery: Previous brain trauma or treatments may increase risk

Preventive Measures and Care

• Healthy Lifestyle: Maintain a balanced diet, exercise regularly, and get adequate sleep
• Environmental Precautions: Limit exposure to radiation and harmful chemicals
• Regular Checkups: Prompt MRI or CT scans if unusual symptoms appear
• Stress Management: Practice relaxation techniques to support overall brain health
• Prompt Treatment: Early consultation with a neurologist or neuro-oncologist for any suspicious signs