Clinical features of patients with small cell lung cancer and idiopathic pulmonary fibrosis treated with chemotherapy or chemoradiotherapy.

Background: The clinical features of patients with small cell lung cancer (SCLC) and idiopathic pulmonary fibrosis (IPF) have not been fully elucidated. Patients and methods: Data on 366 patients with pathologically confirmed SCLC who had been treated with chemotherapy or chemoradiotherapy were retrospectively analyzed to investigate the clinical features of SCLC with IPF. Results: A total of 97 out of the 366 patients were diagnosed with interstitial lung disease (ILD), and 75 of them had IPF. For both the limited disease (LD) and extensive disease (ED) stages, the median progression-free survival (PFS) and overall survival (OS) were significantly shorter in the patients with IPF compared with non-ILD patients. A multivariate analysis showed that poor performance status, ED stage, and the presence of IPF were associated with shorter OS. The response rate to first-line therapy was significantly lower in patients with IPF compared with the non-ILD patients. The rate of patients receiving fewer than three cycles of first-line chemotherapy was higher in patients with IPF, which was a factor of poor survival. In LD-stage patients with IPF, chemoradiotherapy was associated with longer PFS and OS compared with chemotherapy only. Conclusion: In patients with SCLC, the presence of IPF was associated with a lower response rate as well as shorter PFS and shorter OS. There are some cases that are suitable for chemoradiotherapy, even among patients with IPF. The reviews of this paper are available via the supplemental material section.