Clinical study shows benefits of laser therapy for brain tumors

A project at Washington University School of Medicine (WashU Medicine) has completed a study of how laser therapy improves clinical outcomes for brain tumor patients.

Published in the Journal of Clinical Oncology, the findings represent a significant new analysis of the role laser interstitial thermal therapy (LITT) could play in treatment of primary and metastatic brain tumors.

LITT is a MRI-guided procedure primarily designed to use heat to destroy areas of abnormal cells or dead tissues through laser ablation.

The procedure may also have beneficial therapeutic effects beyond tissue removal, as indicated by a Keck Medicine study suggesting LITT brings about transient disruption of the blood-brain barrier and drives local tumor-specific immune responses long after the treatment.

WashU Medicine collected results under the LAANTERN (Laser Ablation of Abnormal Neurological Tissue Registry using NeuroBlate System) clinical study, covering a total of 787 patients. The study employed the NeuroBlate instrumental platform developed by Monteris Medical, and was funded by the company. 

NeuroBlate directs 1064-nanometer irradiation onto target tissues, and has the ability to shape the ablation through directional control of the laser.

"Prior to the LAANTERN study, there was a lack of real-world evidence to support broad care team adoption, payer confidence and guideline inclusion," said Christa Seligman, senior director of clinical sciences at Monteris Medical. "It has been incredibly rewarding to lead a field that once did not have this foundation and to see that effort result in a publication of this caliber."

The researchers aimed to study the largest collected cohort of patients receiving laser surgery for brain tumors that originate in the brain or spread from other parts of the body, so as to understand the factors driving successful patient outcomes of the minimally invasive surgery.

A new framework for handling brain tumors

Findings from the LAANTERN cohort helped to clarify how the extent of tumor destruction was an important factor in patient survival among patients with inoperable or recurrent tumors, especially for those with newly diagnosed glioblastoma. The analysis showed that glioblastoma patients who had at least 91-percent of their tumor cleared survived 2.1 years from diagnosis. 

Because survival with standard open surgical resection is approximately 1.5 years, this provides essential information for considering NeuroBlate as a laser-based tool that can be used to treat these tumors up front.

Beyond glioblastomas the analysis also delivered insights for treating brain metastases, cancers that have spread to the brain from other parts of the body after prior radiation therapy. The data revealed a survival advantage for patients who received laser therapy when the tumors were still small, an insight that re-evaluates the common clinical practice of "watchful waiting" until several imaging cycles have confirmed tumor growth. 

The study provides actionable data to help physicians determine which patients may benefit most from the minimally invasive procedure, commented WashU.

“We are shifting the entire framework of how we handle brain tumors,” said Eric Leuthardt from WashU Medicine. “When patients are told they have months to live, having the option of a low-risk procedure that gets them back home to their families in just over a day is profoundly meaningful.”