Organizing pneumonia adjacent to lung cancer: frequency and clinico-pathologic features

In order to assess the frequency of peripheral organizing pneumonia (OP) in patients with resected lung tumours and to describe its differential features, a cross-sectional study with prospective data collection was realized in a community teaching hospital. Demographic and clinical data were collected from clinical records. The lung specimens removed with a curative purpose in 89 consecutive patients with lung tumours were studied and the clinical and pathological characteristics of patients with and without OP were compared. In 33 of 89 patients (37%) included, OP in the vicinity of neoplasm was found. Areas of other types of fibrosis were evident in 21 patients (24%). Male gender, smoker, epidermoid histological type and the presence of lipid pneumonia were found with a significant higher frequency in patients with OP. Although without significant differences, the presence of symptoms and the bronchial stenosis were found more frequently in patients with OP. In conclusion, OP pattern adjacent to lung cancer, frequently associated to lipid pneumonia, is a common pathological finding. Male gender, a history of tobacco use and epidermoid histological type appear as risk factors for developing this pathologic pattern. Given the lack of distinctive clinico-pathological features, cancer adjacent OP could be confounded with other etiologic forms of this fibrotic process.