Phase 2 64Cu-DOTA-ECL1i CCR2-targeted PET radiotracer imaging in HNSCC.

This prospective, two-cohort precision-imaging study at Washington University School of Medicine evaluates whether 64Cu-DOTA-ECL1i PET/CT—a copper-64–labeled peptide radiotracer that binds CCR2 (C-C chemokine receptor 2) on inflammatory monocytes/macrophages—can sensitively and specifically map CCR2 biology in head and neck squamous cell carcinoma. Cohort 1 enrolls newly diagnosed, resectable T3–T4a/N0–3/M0 HNSCC and performs a single pre-operative scan prior to standard-of-care surgery. Cohort 2 enrolls recurrent/metastatic HNSCC starting first-line anti–PD-1 therapy and repeats the CCR2 PET scan at baseline and again after 3 cycles (within 14 days before cycle 4 day 1) to explore whether CCR2 PET changes track early immunotherapy response. The scientific angle is “immune microenvironment imaging”: CCR2+ myeloid cells can be immunosuppressive, so a CCR2 PET readout could become a noninvasive biomarker to stratify patients or complement tumor-tissue assays; today’s first-line systemic care for recurrent/metastatic HNSCC is pembrolizumab alone in PD-L1–positive disease or pembrolizumab plus platinum/5-FU, while nivolumab is an established option after platinum progression.