Malignant gliomas, including glioblastoma, are among the most aggressive and deadly brain tumours.

Even with surgery, radiation, and chemotherapy, most patients survive little more than a year after diagnosis.

For recurrent tumours, treatment options are extremely limited, and outcomes are often poor.

This harsh reality has fuelled growing interest in alternative therapies that can more precisely target cancer cells while sparing healthy brain tissue.

Boron neutron capture therapy (BNCT), a targeted radiotherapy has emerged as a potential  technique for treatment of recurrent tumours by precise eradication of malignant tumour cells while sparing adjacent healthy tissues.

This therapy involves a boron-containing drug that preferentially accumulates in tumour cells.

The tumour is then exposed to a neutron beam.

When neutrons interact with boron atoms inside cancer cells, they trigger a nuclear reaction that releases high-energy particles capable of destroying the tumour, while minimising damage to surrounding tissue.

In a new study, a team of researchers led by Dr. Chunhong Wang from Peking University, China, and Dr. Zhigang Liu and Dr. Xiao Xu from Southern Medical University, China, provide one of the most comprehensive reviews to date of BNCT for malignant gliomas.

Rather than reporting results from a single clinical trial, the team systematically reviewed decades of clinical studies conducted worldwide to evaluate BNCT's effectiveness, safety, and clinical potential.

The study was published in Volume 9 of the journal Research.

“BNCT is fundamentally different and advantageous compared to conventional radiochemotherapy. It can eliminate both proliferative and  quiescent and hypoxic tumour cells. In addition, BNCT destroys only those cells that have absorbed the neutron capture agent and are irradiated by neutrons. Moreover, the drug involved has low toxicity and minimal side effects,” says Dr. Wang.

To conduct their analysis, the researchers examined clinical trials and case series involving patients with newly diagnosed, recurrent, or treatment-resistant malignant gliomas.

These studies used different boron drugs, most commonly boronophenylalanine, and a variety of neutron sources, including nuclear reactors and more recent accelerator-based systems.

The team assessed outcomes such as overall survival, progression-free survival, and tumour response.

Despite differences in study design and treatment protocols, the findings revealed a consistent trend.

Across multiple studies and regions, BNCT was associated with survival outcomes that compared favourably with standard treatments, particularly in patients with recurrent tumours.

In several reports, median survival times exceeded expectations for this patient group, and a subset of patients achieved long-term survival.

“Preliminary clinical data indicate that BNCT treatment may extend the overall survival and improve the quality of life for patients with glioblastoma, head and neck carcinoma, meningioma, malignant melanoma, and liver cancer,” says Dr. Liu.

The review also highlights BNCT's potential beyond glioblastoma.

Positive outcomes were reported in other high-grade brain tumours, including anaplastic gliomas and malignant meningiomas, suggesting that the therapy may have broader clinical applications.

One key factor driving renewed interest in BNCT is technological progress.

Early BNCT treatments depended on nuclear reactors, while in recent years, accelerator-based neutron sources have been developed, making hospital-based BNCT more feasible and accessible for patients.

While clinical trials have evaluated the potential of BNCT across various tumour types, many of the reviewed studies involved small sample sizes, and treatment protocols varied widely in terms of boron compounds and neutron dose.

These differences affected direct comparison of results across studies.

“Further prospective, well-designed clinical trials with standardised treatment protocols are needed to fully establish the clinical utility of BNCT,” concludes Dr. Xu.

Source: Research