87 Brain tumour surgery presents significant challenges for neurosurgeons, who must balance removing as much of a tumour as possible against the risk of causing neurological injury. This balance is particularly difficult when tumours involve critical brain structures. The corpus callosum, a deep-seated bundle of nerve fibres that serves as the main communication bridge between the brain’s two hemispheres, lies close to important functional pathways, making surgical removal of tumours affecting this area especially complex. IDH-mutant low-grade corpus callosum glioma (ccLGG) is a rare tumour arising from glial cells that support nerve cells in this critical region. Conventional surgery for ccLGG relies on neuronavigation, a technique that maps the three-dimensional location of the tumour using pre-operative MRI images. However, brain shift during surgery can alter the tumour’s position, increasing the risk of damage to adjacent healthy structures or incomplete tumour removal. Newer technologies offer greater precision. Intraoperative MRI (iMRI) captures images directly on the operating table, allowing surgeons to check for any remaining tumour and remove more if needed, while neuromonitoring continuously assesses brain and nerve function, alerting surgeons when they approach critical areas controlling movement, speech, or sensation. A study published in Volume 12 of the Chinese Neurosurgical Journal on 1st May 2026 by researchers from the Chinese People’s Liberation Army General Hospital directly compared conventional neuronavigation-guided surgery with a multimodal approach combining neuronavigation, iMRI, and neuromonitoring. “Few studies have examined the combined effect of these technologies specifically in this rare tumour population,” says senior author Dr Jianning Zhang. The researchers reviewed the medical records of patients diagnosed with IDH-mutant ccLGG who underwent surgery between 2014 and 2022 at their hospital, comparing 64 patients treated using the multimodal approach with 34 patients who underwent conventional surgery. Outcome measures included the extent of tumour removal, neurological function, quality of life, time to tumour progression, and overall survival. “We wanted to find out whether using several advanced surgical technologies together in a multimodal approach helps neurosurgeons remove more of the tumour safely, which factors help patients live longer, and which factors prevent the tumour from coming back,” explains first author Dr Meng Cui. Complete tumour removal was significantly more common with the advanced techniques. The multimodal group achieved a median extent of resection of 100%, compared with 93.55% in the conventional group, while gross total resection rates were 62.5% versus 35.3%. No significant differences were observed in postoperative neurological function or Karnofsky Performance Status between the groups, indicating that the greater extent of tumour removal did not come at the cost of increased disability. Patients in the multimodal group also experienced substantially better long-term outcomes. Median progression-free survival was 78.5 months, compared with 48.1 months in the conventional group, while median overall survival was 106.1 months, versus 66.9 months. The study identified several factors associated with longer progression-free survival, including non-butterfly ccLGG, smaller tumour volume, invasion of the genu of the corpus callosum rather than the splenium, a lower volume of corpus callosum invasion, a greater extent of resection, more cycles of temozolomide chemotherapy, a higher KPS at three months after surgery, and MGMT methylation. Factors associated with longer overall survival included tumour invasion confined to the genu of the corpus callosum, rather than involvement of both the genu and body, a greater extent of resection, more cycles of temozolomide chemotherapy, and MGMT methylation. Patients who received more cycles of temozolomide chemotherapy after surgery tended to have longer survival. Smaller tumours with less extensive spread, those involving only the front part of the corpus callosum (the genu), and non-butterfly tumours were also associated with better outcomes, as were higher KPS scores at three months and MGMT methylation. “This study suggests that, where resources permit, multimodal surgical guidance should be considered for complex gliomas involving critical brain structures,” says Dr Zhang. He adds that broader investment in technologies such as iMRI and neuromonitoring could enable safer removal of challenging tumours such as IDH-mutant ccLGG, supporting more complete resection, longer survival, and extended tumour-free periods while maintaining quality of life.