[Lung cancer in COPD--a clinical analysis]

Recently, increased lung cancer morbidity among patients with chronic obstructive pulmonary disease (COPD) has been observed. There have been efforts to determine the risk factors for lung cancer in these patients. In our study we analyzed smoking history, pulmonary function tests, arterial blood gases and selected laboratory investigations in a group of 46 patients with COPD and primary lung cancer (group I) and compared them to results obtained from 46 randomly selected patients with COPD without lung cancer (group II). The mean number of pack years was higher in group I (55.5 vs 40.0, p < 0.05) and so was the number of patients with severe COPD (55.8% vs 42.1%). We found no differences in ESR, blood count and arterial blood gases, the level of fibrinogen was significantly higher in group I. In 63.4% of the patients lung cancer at stage III and IV was diagnosed. In 15.2% of the patients pathological diagnosis was not established due to severe general condition and low FEV1. We conclude that coexistence of COPD may be a serious obstacle in the diagnosis and treatment of primary lung cancer. Patients with COPD require evaluation for coexistence of lung cancer.