PET [89Zr]DFO-starPEG in Solid Tumors

PRIMARY OBJECTIVES: I. To descriptively report patterns of \[89Zr\]DFO-starPEG uptake on whole-body PET (Cohorts A \& B). II. To determine the radiation dosimetry following \[89Zr\]DFO-starPEG administration (Cohort A). SECONDARY OBJECTIVES: I. To determine the safety of \[89Zr\]DFO-starPEG (Cohorts A \& B). EXPLORATORY OBJECTIVES: I. To study the pharmacokinetics of \[89Zr\]DFO-starPEG and estimate its half-life (Cohort A). OUTLINE: Participants will be assigned to one of 2 cohorts: * COHORT A: Participants will receive multiple scans over time * COHORT B: Participants will receive a scan at a single time point Participants will be followed for adverse events for approximately 1 week after radiotracer administration until the Day 5-9 visit.