Incidence, etiology and clinico-pathologic features of endobronchial benign lesions: 10 consecutive years rerospective study

Introduction. Airways can be largely affected by non-neoplastic lesions including infectious and inflammatory diseases leading to critical stenosis of the lumen. The real-life incidence, etiology and clinical significance of endobronchial benign lesions are not systematically characterized. This study aimed at assessing the epidemiology of non-malignant processes involving the bronchial tree on clinical, pathologic, endoscopic and radiological grounds. Materials and methods. We retrospectively analyzed bronchoscopy procedures over 10 years (January 2005 to December 2014) at the Bronchoscopy Unit of the University Hospital of Modena. All the endoscopically-visible growing benign lesions with histological confirmation were considered, including casesassociated with critical stenosis of the lumen. For each lesion, we evaluated demographics, clinical features and outcome, endoscopic aspect, and radiological characteristic by means of Computed Tomography (CT) as assessed by two experienced radiologists blinded to the diagnosis. Results. Over the study period, we analyzed 10431 bronchoscopies and identified 2,075 cases of tracheobronchial alterations. Among these, 11.2% (n=232) had a benign etiology with an average annual incidence of 23 (range, 16-36) new cases/year and a general incidence of 2.2%. Among all the lesions, 81% (n=1691) was malignant, 7% (n=152) of unknown cause,38% (n=88) was inflammatory, 32% (n=74) infectious, 16% (n=36) were benign neoplasms,and 13% (n=31) iatrogenic diseases. Anthrachosis (36 cases, 15.5%) was the most prevalent bronchial lesion. Twenty-two% of benign lesions presented airway stenosis greater than 50% and required bronchoscopic treatment. The most frequent endobronchial diseases requiring medical treatment were endobronchial tuberculosis (14.2%), sarcoidosis (8.2%) and aspergillosis (10.8%). Bronchial stenosis was most frequently observed in tuberculosis (p=0.031) and aspergillosis (p=0.020) when compared to sarcoidosis. Immunosuppressive status was significantly associated with endobronchial aspergillosis (p=0.0001). Neither diagnosis of tuberculosis, sarcoidosis, and aspergillosis nor the immune system condition influenced one-year survival. Conclusion: A consistent proportion of endobronchial benign lesions is reported from the real-life bronchoscopic procedures. One-fifth of these are associated with critical stenosis of the airway lumen, requiring rigid bronchoscopy intervention. One-year survival was not significantly affected by the host immunity status.