Purpose The aim of the study is to investigate the utilization of photon counting CT (PCCT) and the spectral information provided to determine the impact of spectral information on follow-up examinations. As secondary aims we will compare conventional CT, CT + 18Flouro-deoxy-glucose (18F-FDG) positron emission tomography (PET) and PCCT + 18F-FDG PET for the tumor-node-metastasis (TNM) staging of lung cancer patients. PCCT with and without spectral information to assess the need for additional work-up,TNM classification, and sensitivity/specificity for malignant lesions. Patients will be randomized for reading with or without spectral information available within a clinical setting. The clinical readings are performed as a structured reports of all significant findings. Including both malignant and benign findings. Furthermore, in case additional follow-up/work-up is needed based on the guidelines on incidental findings by the American College of Radiology (ACR), this will be reported as well. If lesions suspicious of pulmonary malignancy is present, a provisional TNM classification is provided based on the scan findings. After 3 months, the patient record is reviewed where additional examinations that can be attributed to the PCCT scan are recorded. The financial impact is calculated by a health economist based on the findings. PET/CT, conventional CT and PCCT combined with PET will be assessed retrospectively for comparison. Endpoints are number of supplementary examinations and cost savings. Sensitivity and specificity for any malignant finding. The T, N and M stages are assessed separately as diagnostic measures by the McNemar's test with a reference standard from the Danish Lung cancer register. The number of malignant lesions will be determined by reviewing the patient records incl. pathology assessment if available 12 months after inclusion of the last patient.