The study aims to induce plastic reorganization by a therapeutic protocol to increase the rate of gross total resection (GTR) and to optimize the oncological result.

Regarding the therapy of cerebral parenchyma tumors, the extent of resection (EOR) has a significant impact on the prognosis. However, total resection is not possible in up to 65% of cases because these tumors frequently infiltrate eloquent areas such as language or motor centers. Consequently, an optimal oncologic result from the surgical perspective cannot be achieved in a considerable large amount of patients. One possible solution is based on the tumor-induced shift of functional areas, which can move away from their original localization. Earlier studies already described the resection of glioma residuals during a second surgery after plastic reorganization has taken place. The authors complained that this reorganization is not detectable without surgery. Navigated transcranial magnetic stimulation (nTMS) was developed for the noninvasive localization of motor and language areas, which enables us to detect the spatial shift of cortical motor and language functions in tumor patients. Recent publications were already able to demonstrate that the individual and exact localization of the motor cortex leads to an increased EOR and prolongs the progression-free survival (PFS). Therefore, the current project intends to take advantage of this plastic reorganization for EOR optimization in cerebral parenchyma tumors. In this context, nTMS is supposed to also induce this plasticity within the frame of a repetitive stimulation protocol (rTMS). Besides other therapeutic applications, rTMS also showed a positive effect on the improvement of aphasia as well as motor recovery in patients after stroke, even in randomized multicenter studies, by inducing plastic reorganization. Moreover, rather than waiting for tumor-induced plastic reorganization, the investigators also aim to use the potential of rTMS for spatial plastic reorganization of functional areas adjacent to intracerebral parenchymal tumors to move functionally eloquent brain regions away from the planned resection cavity.

Inclusion Criteria:

• Intracerebral tumor
• Cortical function is located within planned resection area as confirmed by preoperative navigated transcranial magnetic stimulation and/or intraoperative direct electrical stimulation mapping
• Informed consent for participation
• Age >18 years

Exclusion Criteria:

• Prognosis less than 6 months
• Contraindications for MRI or nTMS (cardiac pacemaker, deep brain stimulator, cochlea implant
• Karnofsky-performance-index <60%

After confirmation by the local ethics committee, individual participant data that underlie the results reported in the manuscript will be available for investigators whose proposed use of the data has been approved by an independent review committee identified for this purpose.

Data will be available after deidentification, beginning nine months and ending 36 months following article publication.

Data will be available for individual participant data meta-analysis. Requestors will need to sign a data access agreement. Information regarding submitting proposals and accessing data will be published. Data will be made available by contacting the corresponding author of this manuscript via email.