Prospective testing of clinical Cerenkov luminescence imaging against standard-of-care nuclear imaging for tumour location

In oncology, the feasibility of Cerenkov luminescence imaging (CLI) has been assessed by imaging superficial lymph nodes in a few patients undergoing diagnostic (18)F-FDG positron emission tomography / computed tomography (PET/CT). However, a weak luminescence signal required the removal of ambient light. Here, we report the development of a clinical CLI fiberscope with a lightproof enclosure, and the clinical testing of the setup using five different radiotracers. In an observational prospective trial (ClinicalTrials.gov identifier NCT03484884) involving 96 patients with existing or suspected tumours with nodal metastases and scheduled for routine clinical FDG-PET or (131)I therapy, the level of agreement of CLI and standard-of-care imaging (PET or planar single-photon emission CT) for tumour location was ‘acceptable’ or higher (≥ 3 in the 1-to-5 Likert scale) for 90% of the patients. CLI correlated with the concentration of radioactive activity, and captured therapeutically relevant information from patients undergoing targeted radiotherapy or receiving the alpha emitter (223)Ra, which cannot be feasibly imaged clinically. CLI could supplement radiological scans, especially when scanner capacity is limited. Prospective testing of a clinical fiberscope with a lightproof enclosure for Cerenkov luminescence imaging using five different radiotracers showed satisfactory agreement with standard-of-care nuclear imaging for tumour location.