Effect of Impaired Lung Function on the Development and Progression of Endobronchial Premalignant Lesions

Background: Chronic obstructive pulmonary disease (COPD) and the presence of endobronchial premalignant lesions (EPL) are individual risk factors for lung cancer (LC). However, effect of impaired lung function (ILF) on the natural history of EPL has not been explored. Patients and Methods: This study included 217 high-risk participants from a hospital-based LC surveillance cohort who underwent pulmonary function testing followed by bronchoscopy with endobronchial biopsies. Baseline histopathology diagnoses included 91 cases (41.9%) with squamous metaplasia (SM), 25 (11.5%) with squamous dysplasia (SD), 1 (0.5%) with in-situ carcinoma and 5 (2.3%) with invasive LC. Follow-up biopsies were obtained for 69 patients, and 16 (23.2%) patients demonstrated progression to a higher grade lesion. Regression models were used to evaluate the relationship between ILF and EPL. All the models were adjusted for age, gender and tobacco smoking. Results: Patients with FEV1% of <50% had 4.5 times greater risk of being diagnosed with an EPL [95% confidence interval: 1.93 10.80] and 8-fold greater risk of SD, compared to patients with FEV1% ≥ 80. COPD was associated with 2.7 and 4.8 times greater risk of SM and SD, respectively. The mean time to progression to a higher-grade lesion was shorter in COPD patients compared to patients without COPD (27 versus 50 months, p = 0.02). Conclusion: Our results indicate that ILF may be a predictor of prevalence and progression of EPLs among patients at high risk of LC. Therefore, spirometry can be a complementary pre-screening tool for identifying patients with EPL who need more intense LC surveillance.