Compared to other Western countries there is a much higher incidence of several types of cancers in Eastern and Central Europe. A large multinational hospital-based case-control study of lung, kidney and oesophageal cancers, co-ordinated by IARC, is in progress to identify some of the risk factors that may be involved. This paper reports preliminary results from the Prague centre that focus on the risk factors for lung cancer. According to the study protocol all cases had to be admitted at a collaborating clinic. Within 3 months patients were asked to sign an informed consent form and complete the study questionnaire with the help of a nurse. They were asked to give a blood sample and, if circumstances permitted, a fresh tissue sample. Data from the questionnaire were entered into 3 databases: lifestyle, occupational and clinical. Identification of risk factors related to the indoor environment was the aim of the first part of the lifestyle questionnaire. Several risk factors for lung cancer, such as smoking, are well-known. Our study showed other associations between lung cancer incidence and lifestyle-related factors, such as education status, which is generally an indicator of socio-economic status. Solid fuel burning was confirmed as a potential risk factor. A significant association between incidence and partner smoking was observed in non-smokers also an inverse association (trend) between lung cancer incidence and the size of the subject's community, which appeared consistent for both smokers and non-smokers. © 2005 Sage Publications.