Intraoperative real-time MRI-guided stereotactic biopsy followed by laser thermal ablation for progressive brain metastases after radiosurgery.

Stereotactic radiosurgery is one of the treatment options for brain metastases. However, there are patients who will progress after radiosurgery. One of the potential treatments for this subset of patients is laser ablation. Image-guided stereotactic biopsy is important to determine the histopathological nature of the lesion. However, this is usually based on preoperative, static images, which may affect the target accuracy during the actual procedure as a result of brain shift. We therefore performed real-time intraoperative MRI-guided stereotactic aspiration and biopsies on two patients with symptomatic, progressive lesions after radiosurgery followed immediately by laser ablation. The patients tolerated the procedure well with no new neurologic deficits. Intraoperative MRI-guided stereotactic biopsy followed by laser ablation is safe and accurate, providing real-time updates and feedback during the procedure.

The role of salvage reirradiation for malignant gliomas that progress on bevacizumab.

Bevacizumab and irinotecan are effective against recurrent malignant gliomas. However, at subsequent progression, patients rarely respond to a second bevacizumab-containing chemotherapeutic regimen. Salvage re-irradiation with bevacizumab for recurrent but bevacizumab naive malignant gliomas showed encouraging results. We performed a retrospective review of the medical records of 23 patients treated with either fractionated stereotactic radiotherapy (FSRT) or stereotactic radiosurgery (SRS) after progression on an initial bevacizumab regimen. Patients were treated after re-irradiation with bevacizumab but combined with a different chemotherapy. We then compared them to another 23 patients who progressed on an initial bevacizumab + chemotherapy regimen. These patients did not receive re-irradiation but bevacizumab was continued combined with a different chemotherapy. Patients treated with FSRT/SRS/bevacizumab had a longer median progression-free period (2.6 vs. 1. 7 months, P = 0.009), longer median post FSRT/SRS treatment survival (7.2 vs. 3.3 months, P = 0.03) and higher radiographic response rate (22 vs. 0%, P = 0.049). FSRT or SRS followed by bevacizumab + chemotherapy may have a role for patients who progress on bevacizumab.