Survival after surgery for clinical stage I non-small-cell lung cancer with interstitial pneumonia

Objectives: To evaluate the surgical outcomes after surgery in patients with stage I lung cancer and idiopathic interstitial pneumonia (IIP). Material and methods: This retrospective cohort study was conducted in 2131 patients with clinical stage I nonsmall-cell lung cancer (NSCLC) who underwent pulmonary resection between 2009 and 2018. Based on computed tomography (CT) findings, 233 patients had IIP. Lobectomy was performed in 180 patients with IIP and 1227 patients without IIP. Surgical outcomes, recurrence sites, and cause of death were investigated. In addition, we measured the distance between the tumor and hilum in patients with IIP and assessed the feasibility of sublobar resection. Results: The overall survival and cancer-specific survival of patients with IIP were significantly poorer than those of non-IIP patients. The five-year overall survival rates of patients with clinical stage IA/IB lung cancer with and without IIP were 58.1%/47.3% and 88.8%/68.9%, respectively. Furthermore, 9.4% of patients with IIP and 0.9% of patients without IIP died from respiratory-related causes within 2 years after surgery. Multivariate analyses revealed that volume capacity <80% (odds ratio: 3.259), usual interstitial pneumonia pattern by CT finding (odds ratio: 1.891), and nodal metastasis (odds ratio: 3.304) were prognostic factors for overall survival in patients with IIP. Unexpected nodal metastases were observed in 22.3% of patients with IIP. By CT judgment, sublobar resection was not feasible in 68% of patients with IIP who underwent lobectomy. Conclusions: The overall survival of patients with early NSCLC after pulmonary resection with IIP was poor; this is related to the high prevalence of cancer-specific and respiratory-related deaths. Sublobar resection is not always feasible, the procedure on patients with IIP should be selected carefully according to the characteristics of each case. Nodal dissection should be performed to evaluate for metastasis, regardless of the extent of lung resection.