Primary endpoints of this protocol are to demonstrate feasibility of an optimized, image-guided pre-planned workflow to deliver at least 25 Gy to the periphery of the target lesion while maintaining established dose constraints to normal tissues, and then to determine the maximum tolerated dose (MTD) of navigated percutaneous interstitial HDR brachytherapy for liver lesions. Secondary endpoints include assessment of toxicity and oncologic outcome (primarily local control at the treated site) and exploratory endpoints will be supported by advanced imaging studies at the time of the treatment procedure.~The 25 Gy starting dose was chosen as it has been shown to be effective at controlling tumor, albeit with limited followup. The promising outcomes noted at that dose are predicated on actually delivering that dose, hence the feasibility endpoint for meeting the goal dose delivery. While the other primary endpoint will be toxicity so as to avoid exceeding the MTD, this trial will treat more patients at each level to better characterize both toxicity and efficacy within a dose level (the therapeutic window). The investigators will attempt to escalate to levels that modeling would predict to have durable local control approaching 100%.55 Dose escalation levels of 5 Gy were chosen to mirror other studies performed at this institution with SBRT
The objectives of this study are to demonstrate feasibility of an optimized, image-guided pre-planned workflow to deliver at least 25 Gy to the periphery of the target lesion while maintaining established dose constraints to normal tissues, and to determine the maximum tolerated dose (MTD) while evaluating treatment delivery, safety, and efficacy utilizing a pre-planned and optimized image-guided workflow for percutaneous HDR brachytherapy of liver lesions.