title: Detection rate of lung cancer among chronic obstructive pulmonary disease patients regularly followed up by pulmonary physicians.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) has been found to be an independent risk factor for lung cancer. The aim of this study was to evaluate whether regular follow up of COPD patients increases the diagnosis of lung cancer at an early stage.
  
  
  METHODS
  Case reports of 105 male moderate to severe COPD patients who participated in a clinical study were analyzed retrospectively. Throughout the 3-year study period patients regularly visited a pulmonary physician. Investigations to detect lung cancer were ordered only with the presence of symptoms. The lung cancer incidence in the study group was compared to that of general male population matched by age.
  
  
  RESULTS
  At the beginning of the study the mean age was 67 (range 55-81) years, mean smoking history 36.2 (range 11-102) years and mean forced expiratory volume in 1 s (FEV1) 43.3% (range 22.7-59.7). During the study six lung cancers and five other cancers were diagnosed per 287 person-years of observation. Only one lung cancer was operable, others were locally advanced or had distant metastases.
  
  
  CONCLUSIONS
  Despite the patients being followed up regularly by a pulmonary physician, most cancers were diagnosed at an advanced stage. The relative risk of getting lung cancer was 6.0 times higher (95% CI 2.7-13.3) among COPD patients than among the general population. The current study confirms that COPD patients have an increased risk of lung cancer. Moreover simple regular follow up of patients without special lung cancer screening investigations do not help to detect the cancer in its early stage. This study stresses the need to establish a more detailed follow-up program for COPD patients to detect early lung cancer in this high risk population.
authors.affiliation: Department of Thoracic Surgery, Tartu University Hospital, Tartu, EstoniaDepartment of Pneumology, Tartu University Hospital, Tartu, Estonia.
authors.forename: Tanel
authors.initials: T
authors.lastname: Laisaar
authors.affiliation: Department of Thoracic Surgery, Tartu University Hospital, Tartu, EstoniaDepartment of Pneumology, Tartu University Hospital, Tartu, Estonia.
authors.forename: Hille
authors.initials: H
authors.lastname: Lill
authors.affiliation: Department of Thoracic Surgery, Tartu University Hospital, Tartu, EstoniaDepartment of Pneumology, Tartu University Hospital, Tartu, Estonia.
authors.forename: Anneli
authors.initials: A
authors.lastname: Kullamaa
authors.affiliation: Department of Thoracic Surgery, Tartu University Hospital, Tartu, EstoniaDepartment of Pneumology, Tartu University Hospital, Tartu, Estonia.
authors.forename: Rain
authors.initials: R
authors.lastname: Jõgi
keywords: Chronic obstructive pulmonary disease; incidence; lung cancer; smoking