Patients who are admitted to the outpatient pulmonology department by a general practitioner or specialist with a chest X-ray suspicious for lung cancer with an age between 18 and 80 years are suitable for participation. The X-ray and referral are studied by a chest physician (by phone or fax ). Selected patients are invited to enter the study after answering a questionnaire by phone (p. 31). The questionnaire screens patients' interest, co-morbidity and medication use. Informed consent forms, patient information forms and a time table for the diagnostic day are provided by mail or E-mail in cases where time gets short. Waiting time to enter the study will be no longer than one week.