Experimental: study treatment plan

Patients will be enrolled in a Rolling 6 clinical trial design1. This study design retains sensitivity to identifying DLTs while having the benefit of decreasing accrual time given the long DLT period required to assess radiation toxicity. In this trial design, up to 6 patients can be enrolled at a time onto a dose level while awaiting DLT assessment. Established rules guide the decision for enrolling onto the current, next highest, or previous dose level based on the number of participants currently enrolled in a given cohort, the number of radiation-attributable dose-limiting toxicities (ra-DLTs) observed, and the number of patients with immature toxicity data. If the MTD is not reached after 6 patients have enrolled on dose level 3 (three 17Gy fractions of SBRT) and have completed toxicity evaluations, then the recommended phase 2 dose will be determined based on an analysis of the efficacy of the combination