GammaTile therapy results in improved clinical outcomes; however the data is a single site experience with a limited number of subjects, only 12 of which were patients with metastatic brain tumors. The primary objective of this randomized, controlled trial is to compare the efficacy and safety of intraoperative radiation therapy using GammaTilesTM (GT) versus SRS 3-4 weeks following metastatic tumor resection which is the current standard of care. The data collected in this trial design will allow for a direct comparisons of a variety of outcomes including local control, overall survival, functional status, quality of life, neurocognitive status and safety in the target population. In order to support direct comparisons, subjects will be randomized to the two equally sized arms (1:1) based on the following stratification factors; age (<60 and ≥60), duration of extracranial disease control (≤3 months vs >3 months), number of metastases (one or two to four), histology (lung and radiation resistant), and the maximal diameter of the index lesion (≤3 cm and >3 cm).~An index lesion meeting the criteria of 2.5cm to 5cm in diameter and appropriate for gross total resection (GTR), will be identified and up to three other non-resectable lesions in a patient will be allowed. After resection of the index lesion the surgical bed will be treated with adjunct radiation (either GT or SRS) thereby following the standard of care guideline. (NCCN Guidelines, 2019). Additional unresected metastatic lesions will be treated with with stereotactic radiosurgery alone, which also adhears to standard of care guidelines.(NCCN Guidelines, 2019).~GammaTile is an FDA-cleared means of rapid dose delivery of radiation therapy directly to the tumor bed with predictable dosimetry at the immediate time of re-resection, and a intense but localized radiation treatment may confer a reduced risk for radiation necrosis compared to other therapies. It is typically easly placed with minimal additional operative time and limited staff radiation exposure.~Given these benefits, the rationale for conducting this randomized control comparison study is to generate additional data, to further support the use of this new FDA-cleared method of delivering radiation therapy in the setting of newly diagnosed brain metastases.
This trial will be a randomized controlled study comparing the efficacy and safety of intraoperative radiation therapy using GammaTilesTM (GT) versus SRS 3-4 weeks following metastatic tumor resection which is the current standard of care.