Awake mapping-guided salvage resection for local recurrence or radiation necrosis after stereotactic radiosurgery and radiotherapy for brain metastases.

PURPOSE: Local recurrence or radiation necrosis after stereotactic radiosurgery or stereotactic radiotherapy (SRS/SRT) for brain metastases often presents a surgical challenge because of unclear lesion boundaries and high risk in the case of lesions proximal to eloquent areas. Here, we retrospectively evaluated the feasibility and usefulness of awake surgery as salvage treatment for recurrent lesions after SRS/SRT.

METHODS

Between June 2020 and August 2025, 11 awake surgeries in 10 patients for local recurrence or radiation necrosis after SRS/SRT for brain metastases were retrospectively reviewed. All surgeries were performed using cortical and subcortical mapping, similar to procedures for glioma surgery, with the aim of maximal safe resection. Clinical characteristics, pathological findings, neurological outcomes, and postoperative courses were analyzed.

RESULTS

The cohort included 10 patients (mean age: 69.2 ± 7.9 years). The mean time from SRS/SRT to awake surgery was 793 ± 615 days. Primary tumors were derived from the lung, kidney, thyroid, ovary, and esophagus. All awake surgeries were successfully performed. Gross total resection was achieved in all, except for two, patients. The pathological diagnosis was recurrence in seven cases and radiation necrosis in four cases. Postoperative neurological function was preserved in the majority of cases, although one patient experienced transient worsening of motor weakness during the final stage of resection. Local control was achieved in all cases except one case, with no recurrence observed during long-term follow-up in selected patients.

CONCLUSION

Awake surgery is a feasible and useful salvage strategy for failed brain metastases after SRS/SRT, particularly when lesions are located in or near eloquent areas. In addition, this approach allows maximal safe resection under functional monitoring in situations where lesion boundaries are unclear due to prior radiation.