The leading European and American professional societies recommend that bone scans (BS) should be performed in the staging of lung cancer only in those patients with bone pain. This prospective study investigated the sensitivity of conventional skeletal scintigraphy in detecting osseous metastases in patients with lung cancer and addressed the potential consequences of failure to use this method in the work-up of asymptomatic patients. Subsequent to initial diagnosis of non-small cell lung cancer, 100 patients were examined and questioned regarding skeletal complaints. Two specialists in internal medicine decided whether they would recommend a bone scan on the basis of the clinical evaluation. Skeletal scintigraphy was then performed blinded to the findings of history and physical examination. The combined results of magnetic resonance imaging (MRI) of the vertebral column, positron emission tomography (PET) of skeletal bone and the subsequent clinical course served as the gold standard for the identification of osseous metastases. Bone scintigraphy showed an 87% sensitivity in the detection of bone metastases. Failure to perform skeletal scintigraphy in asymptomatic patients reduced the sensitivity of the method, depending on the interpretation of the symptoms, to 19-39%. Without the findings of skeletal scintigraphy and the gold standard methods, 14-22% of patients would have undergone unnecessary surgery or neoadjuvant therapy. On this basis it is concluded that bone scans should not be omitted in asymptomatic patients.