89Zr-olaratumab Dosimetry in Participants With PDGFR Alpha Positive Solid Tumours and Soft Tissue Sarcoma

This study uses a special radioactive imaging agent called 89Zr-olaratumab to scan soft tissue sarcomas (rare cancers of muscle, fat, or connective tissue). The goal is to understand how much of the drug reaches the tumor and how it behaves in the body, which is important for developing it as a future targeted treatment. **You may be eligible if...** - You are 18 or older with a confirmed soft tissue sarcoma - You have at least one tumor larger than 2 cm visible on standard imaging - Your blood counts and organ function meet minimum safety thresholds - You are willing to provide a tumor tissue sample (or have one archived) **You may NOT be eligible if...** - Your tumor cannot be biopsied or imaged adequately - Your organ function is too poor to safely receive the imaging agent Talk to your doctor to see if this trial is right for you.