Bronchial colonisation in patients with lung cancer: a prospective study

Bronchial colonisation is frequently reported in patients with lung cancer, and has a potential impact on therapeutic management and prognosis. We aimed to prospectively define the prevalence and nature of bronchial colonisation in patients at the time of diagnosing lung cancer. 210 consecutive patients with lung cancer underwent a flexible bronchoscopy for lung cancer. The type and frequency of bacterial, mycobacterial and fungal colonisation were analysed and correlated with the patients' and tumours' characteristics. Potential pathogens were found in 48.1% of samples: mainly the Gram-negative bacilli Escherichia coli (8.1%), Haemophilus influenzae (4.3%) and Enterobacter spp. (2.4%); Gram-positive cocci, Staphylococcus spp. (12.9%) and Streptococcus pneumoniae (3.3%); atypical mycobacteria (2.9%); Candida albicans (42.9%); and Aspergillus fumigatus (6.2%). Aged patients (p=0.02) with chronic obstructive pulmonary disease (p=0.008) were significantly more frequently colonised; however, tumour stage, atelectasis, bronchial stenosis and abnormalities of chest radiography were not associated with a higher rate of colonisation. Squamous cell carcinoma tended to be more frequently colonised than other histological subtypes. Airway colonisation was reported in almost half of patients presenting with lung cancer, mainly in fragile patients, and was significantly associated with worse survival (p=0.005). Analysing colonisation status of patients at the time of diagnosis may help improve the management of lung cancer.