18F-FDG PET/CT is an useful diagnostic tool for cancer patients. In our routine practice, we perform a significant number of PET/CT scans in association with contrast enhanced CT, to assess resectability of abdominal tumors or to evaluate distant brain and liver metastases. We documented an unexpected emergency disease during a contrast enhanced 18F-FDG PET/CT. In a 63-year-old male patient, examined during follow-up of lung cancer, no sites of disease relapse were detected at PET/CT; nevertheless, diffuse tracer uptake was detected along the outline of a biliary stent. Correlative contrast enhanced CT diagnosed fracture of a metallic biliary stent without any evidence of cancer involvement. Patient was referred to the local department of surgery for substitution of the biliary stent. Although rare, unexpected emergency diseases requiring urgent management are detected using 18FFDG PET/CT. Correlative CT should be carefully evaluated in order to avoid delays in diagnosis, potentially leading to poorer prognosis.