Worse lung cancer outcome in patients with lower respiratory tract infection confirmed at time of diagnosis

BACKGROUND: Pulmonary malignancy is one of the most frequent and fatal cancers in older patients. As data on lower respiratory tract infection (LRTI) and the outcome of lung cancer are scarce, our objective was to determine the impact of LRTI on therapeutic possibilities and one-year mortality. METHODS: Patients undergoing bronchoscopy in 2017 who had bronchial microbial sampling at the time of the lung cancer diagnosis (n = 143) were included. Group 1 (LRTI+) included patients with confirmed infection (n = 74) while Group 2 (LRTI-) included patients without infection (n = 69). Clinical characteristics, pathogen profile and one-year survival were analyzed. RESULTS: Age, gender, TNM stage, histology type, comorbidities or underlying lung disease did not differ among groups. The most common LRTI pathogens included aerobic (n = 49), anaerobic (n = 14) and fungal (n = 26) infections. Chemo/immune/target therapy alone, or in combination with radiotherapy were significantly less frequently used, whilst palliative care was more common in Group 1 (LRTI+). Multiple pathogen LRTI patients were significantly older, less frequently diagnosed with adenocarcinoma and had worse performance status compared to solitary pathogen LRTI patients. One-year median survival was 274 days (235 vs. 305 days Group 1 vs. Group 2). Risk factors for increased one-year mortality included performance status ≥2 (OR 30.00, CI 95% 5.23-313.00), performance status 1 (OR 11.87, CI 95% 4.12-33.78), male gender (OR 4.04, CI 2.03-8.04), LRTI with multiple pathogens (OR 2.72, CI 1.01-6.81) and nonadenocarcinoma histology (OR 2.26, CI 1.15-4.56). CONCLUSION: LRTIs in lung cancer patients, especially multiple pathogen infections, are associated with less oncotherapeutic possibilities and significant risk for lower one-year median survival.