Objective: 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ([18F]-FDG PET/CT) can be developed in association with contrast-enhanced CT (ceCT), specifically in oncologic patients. This study aimed to evaluate emergency cases incidentally detected in our clinical practice with [18F]-FDG PET/ceCT. Method: We retrospectively evaluated 3661 [18F]-FDG PET/ceCT, developed between 2017 and 2023, collecting emergency cases needing prompt treatment. Results: In 34/3661 patients (0.9%) an emergency case was recorded, in particular through contrastenhanced CT, linked to a vascular (65%) or extravascular (35%) disease. The more frequent findings were pulmonary thromboembolism (0.5%). [18F]-FDG PET/CT was positive in 13/34 cases. Conclusions: A significant minority of patients undergoing PET/ceCT present vascular or extravascular emergency diseases. The [18F]-FDG uptake improves confidence in diagnosing inflammatory findings. Properly trained diagnostic physicians approaching PET/ceCT can change the prognosis of a small but significant number of cancer patients through a life-saving approach. Future studies are needed to ensure the possibility of emergency findings with non-[18F]-FDG tracers.  Kulcsszavak: contrast-enhanced CT, emergency findings, hybrid imaging, PET/CT, [18F]-FDG