Incidence of cancer in patients with IPF.A retrospective multicenter study

Background: Abundant evidence supports an association between Idiopathic Pulmonary Fibrosis (IPF) and lung cancer development. Nevertheless, the incidence of other types of cancer in patients with IPF is still unknown. Aim: To assess incidence of lung and other types of cancer in patients with IPF. Patients and Methods: This was a retrospective study using data from two different centers. Between September 2011 and September 2016, we identified patients with IPF which developed, histologically confirmed, lung or other types of cancer. Diagnosis of IPF was based on ATS/ERS 2013 criteria. Results: We identified 33 cases of patients with IPF and cancer (incidence=11.8%, 33/271), of mean age+SD=71.9+7.1, 32 males. There were 23 (69.6%) patients with non-small cell lung cancer, the majority of whom were adenocarcinoma (n=13, 56.5%). There were 3 cases (9.1%) of small cell lung cancer and 7 (21.2%) cases of other cancers including colon (9.3%), stomach (3.1%) and breast cancer (3.1%). Regarding other comorbidities, our analysis revealed the following: Fourteen (n=14) patients had combined pulmonary fibrosis and emphysema (42.4%), 18 gastroesophageal reflux symptoms (54.5%), 10 pulmonary (30.3%) and 17 arterial hypertension (51.5%). Patients had mild-to-moderate disease severity as assessed by pulmonary function tests (meanFVC+SD: 77.2+22.5, meanDLCO+SD: 50.6+15.3). Median survival was 851 days (95%CI: 600.4 to 1253.1) and 11 patients (33.3%) died within the follow-up period. Conclusions: Our epidemiologic data validates previously published results and identifies IPF as a risk factor for different types of cancer development irrespective of disease severity. Further studies are warranted to support this notion.