CONNEctome-guided Navigation for Eloquent-area Tumor Surgery Trial

This is a prospective, randomized, controlled superiority trial designed to evaluate whether connectome-guided navigation-assisted microsurgical resection improves postoperative functional preservation in patients with tumors located in eloquent brain regions when compared with conventional tractography-guided surgery.

Brain tumors involving language areas, motor areas, or key large-scale functional networks present a major surgical challenge because maximal resection must be balanced against preservation of neurological function. Conventional neuronavigation based mainly on structural landmarks or tractography may be insufficient to fully characterize the topological relationship between the tumor and critical functional networks. This study therefore applies a connectome-informed surgical strategy that integrates preoperative structural and functional imaging with intraoperative guidance to support individualized surgical planning and functional protection.

Eligible patients are those with brain tumors involving language, motor, or major functional network regions, including the default mode network, central executive network, dorsal attention network, and ventral attention network, with Karnofsky Performance Status of at least 70 and preoperative MRI evidence of a spatial relationship between the tumor and major white matter tracts. Patients with non-neoplastic lesions, multifocal tumors, incomplete evaluation data, pregnancy-related conditions, or extensive adhesion to multiple key network nodes are excluded.

Participants are randomized in a 1:1 ratio to the experimental group or the control group. The experimental intervention includes preoperative DTI and resting-state functional MRI-based brain network reconstruction, intraoperative real-time navigation, electrophysiological monitoring, and resection planning based on network-informed boundaries. The control intervention consists of conventional DTI tractography-guided tumor resection.

The primary endpoint is postoperative functional preservation. Secondary endpoints include extent of resection, postoperative complication rate, time to neurological recovery, overall survival, progression-related outcomes, and quality of life. Exploratory analyses will assess postoperative dynamic changes in brain networks and functional compensation mechanisms using multimodal MRI data, including resting-state functional MRI and diffusion imaging.

Study assessments are performed at baseline, within 24 to 72 hours after surgery, and during postoperative follow-up at 1 month, 3 months, 6 months, and 1 year. MRI is used to evaluate extent of resection, while neurological examinations, performance scales, and clinical rating instruments are used to assess functional outcomes over time. Quality of life is assessed using validated cancer-related instruments during follow-up.

The planned total sample size is 200 participants, with 100 patients in each group, based on a superiority design using postoperative functional preservation as the primary endpoint. Data will be analyzed using predefined statistical methods, including descriptive statistics, between-group comparisons, survival analysis, and modeling of factors associated with postoperative neurological impairment.

Inclusion criteria

• Patients clinically diagnosed with brain tumors involving language areas, motor areas, or major functional brain networks, including the default mode network, central executive network, dorsal attention network, or ventral attention network.
• Karnofsky Performance Status (KPS) score of 70 or higher.
• Preoperative MRI demonstrating a spatial relationship between the tumor and major white matter tracts, such as the corticospinal tract or arcuate fasciculus.
• No other neurological disease or underlying condition that may cause neurological dysfunction.
• No prior treatment for a brain tumor in the same region, such as radiotherapy.
• Tumor not extensively adherent to multiple critical network nodes.
• Planned craniotomy for tumor resection and provision of written informed consent by the patient or legally authorized representative.

Exclusion criteria

• Pathologically or clinically suspected non-neoplastic brain lesion.
• Multifocal tumors.
• Incomplete evaluation data.
• Withdrawal from the study by the patient or legally authorized representative for any reason.
• Pregnancy, lactation, possibility of pregnancy, or planned pregnancy.