This is a dose-escalation study where the objective is to find the Maximum Tolerated Dose (MTD) and Recommended Phase 2 Dose (RP2D) of adaptive SBRT for abdominopelvic SBRT. There are 3 doses of interest 8Gy/fraction (level 1), 9Gy/fraction (level 2), and 10Gy/fraction (level 3). The starting dose will be level 2. We will use a Bayesian Optimal Interval Design (BOIN) to define dose escalation and de-escalation rules based on the proportion of patients experiencing a dose-limiting toxicity (DLT). DLT events are Grade 3 events possibly, probably, or definitely related to the study intervention.
Single arm Phase I trial of adaptive stereotactic body radiation (SBRT) for abdominopelvic metastases. Adaptive SBRT will allow for escalation of the prescription dose and target coverage while maintaining grade 3+ toxicity no greater than 10%. Subjects with metastatic cancer to the abdomen or pelvis requiring local control or palliation will be enrolled.