Exhaled breath condensate pH in patients with lung cancer.

Assessment of exhaled breath condensate (EBC) pH is a promising method for investigating and monitoring airway pathology in a number of lung diseases. In this cross-sectional study we tested whether development of lung cancer is associated with acidification of EBC. EBC was collected in 43 smoking patients with lung cancer (squamous cell carcinoma: 17 patients, adenocarcinoma: 16 patients, and small cell lung cancer: 10 patients) before receiving any anticancer treatment and in 20 healthy smokers without any clinical and radiological evidence of pulmonary tumor. EBC pH was measured by CO(2) gas standardization, the most reliable and accurate method at present. EBC pH in patients with pulmonary tumor (6.68±0.02) and in controls (6.63±0.05) was similar (p>0.05). Results were affected neither by the histological subtype nor the stage of the tumors. Our data suggest that assessment of EBC pH is of limited value for the diagnosis and/or screening of lung cancer.