The study focuses on patients with unresectable stage III non‑small cell lung cancer, a form of lung cancer that cannot be removed by surgery and is at an advanced stage. The investigational treatment is a version of the immunotherapy drug durvalumab that has been attached to a fluorescent marker and is referred to as durvalumab‑680LT. This drug is given by an intravenous (IV) infusion, meaning it is delivered through a needle placed in a vein. All participants also receive standard chemoradiation, which is a combination of chemotherapy drugs and radiation therapy used to shrink the tumor before the new drug is examined.
The purpose of the study is to see how the fluorescent drug spreads inside the tumor and nearby lymph nodes after chemoradiation but before regular durvalumab treatment begins. Participants undergo a procedure called fluorescence molecular bronchoscopy, where a thin, flexible tube with a special camera is inserted through the airway to look directly at the lungs and lymph nodes. The camera detects the glow from the drug, and the brightness is expressed as a tumor‑to‑background ratio, a simple number that compares how bright the tumor appears to the surrounding tissue; a higher number indicates better drug presence in the tumor.
After the bronchoscopy, patients are monitored for any side effects and have routine follow‑up visits to track their health over time. No additional experimental treatments are given beyond the standard care and the single imaging procedure. The information collected will help researchers understand where the drug goes in the body, which may guide future use of immunotherapy for this type of lung cancer.
The Netherlands 
