LAUSR

OBJECTIVE Posterior fossa tumors are rare in adults and pose a challenge to treat due to the bony contour of the posterior fossa, complex anatomical structures including deep venous sinuses, and the proximity of the fourth ventricle and brain stem. We describe our experience with LITT for the management of brain metastases and radiation necrosis of the posterior fossa. METHODS We retrospectively analyzed 13 patients with metastases and radiation necrosis of the posterior fossa managed with LITT. RESULTS Thirteen patients with histopathologically-confirmed radiation necrosis (n = 5) and metastases (n = 8) of the posterior fossa underwent LITT. The median preoperative tumor and postoperative ablation cavity volume was 4.66 cm3 and 6.29 cm3, respectively. The median volume of the ablation cavity decreased to 2.90 cm3 at 9-month follow-up. The median volume of peritumoral edema was 12.25 cm3 which fell to a median 5.77 cm3 at one-month follow-up. Median progression-free survival was 7 months (range 3 - 14 months) from LITT. The mean overall survival (OS) was 40 months (range 2 - 49 months). There were no intraoperative complications. One patient experienced palsy of the seventh and eighth cranial nerves on follow-up, attributable to LITT. CONCLUSION Lesions of the posterior fossa are challenging to treat given their proximity to the dura and venous sinuses. We demonstrate that LITT ablation may be a safe and feasible option for metastases and radiation necrosis of the posterior fossa. Larger studies are needed to confirm the efficacy of this approach.