271 - Outcomes of SABR or Surgery for Early-Stage Lung Cancer in Patients with Interstitial Lung Disease (ILD)
Presenter(s)
M. L. Tomassen1, S. F. M. Nijman2, E. J. Nossent2, C. Dickhoff3, O. M. Mets4, T. Radonic5, B. G. Boerrigter2, M. van Dorp3, D. J. Heineman3, M. I. Ronden - Kianoush6, I. Bahce2, C. Haasbeek1, F. L. Schneiders1, J. J. C. Verhoeff1, P. S. N. van Rossum1, and S. Senan1; 1Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Radiation Oncology, Amsterdam, Netherlands, 2Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Pulmonology, Amsterdam, Netherlands, 3Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Thoracic Surgery, Amsterdam, Netherlands, 4Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Radiology, Amsterdam, Netherlands, 5Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Pathology, Amsterdam, Netherlands, 6University Medical Center Groningen, Department of Radiation Oncology, Groningen, Netherlands
Purpose/Objective(s):
The ASPIRE-ILD study (n=39) reported that stereotactic ablative radiotherapy (SABR) is a viable treatment for selected patients with early-stage non-small cell lung cancer (NSCLC) and interstitial lung disease (ILD). Other small prospective series, such as WJOG-6711L (n=39), suggest surgery is also safe for selected patients. However, real-world data on treatment patterns and long-term outcomes in a broader ILD-lung cancer population are limited. We studied outcomes of SABR and surgery in patients managed by a dedicated ILD-lung cancer team at an academic center.Materials/Methods:
A retrospective cohort study evaluated ILD patients with stage I-II NSCLC or small cell lung cancer (SCLC) at our tertiary referral center in 2006-2024. A multidisciplinary tumor board specializing in ILD and thoracic malignancies was established over a decade ago. Patients treated with SABR or surgery were analyzed. Primary endpoints included overall survival (OS) and progression-free survival (PFS), calculated from lung cancer diagnosis. OS and PFS were analyzed using Kaplan-Meier estimates with log-rank tests. Secondary outcomes included treatment-related toxicity and complications (e.g., ILD exacerbations, radiation pneumonitis, surgical complications).Results:
Of 125 ILD patients with lung cancer, 78 had stage I-II disease. The 68 patients receiving surgery (n=33) or SABR (n=35) were included. Surgical patients were younger (median 70 vs. 77 years, p=0.004) and had better WHO performance status (p=0.006). Idiopathic pulmonary fibrosis (IPF) was the most common ILD (31% vs. 35%, p=0.250). Concurrent anti-fibrotic therapy was more common in surgery patients (45% vs. 20%, p=0.025). Median follow-up was 28.5 months (95% CI 23.7-33.3). One-year OS was 90.1% (95% CI 79%-100%) in surgical patients (median OS 32.0 months, 95% CI 26.8–37.3) and 71% (95% CI 56%-86%) in SABR patients (median OS 26.6 months, 95% CI 19.5–33.7; p=0.077). One-year PFS was 61% (95% CI 45%-76%) with surgery (median PFS 28.3 months, 95% CI 8.5–48.2) and 68% (95% CI 54%-83%) with SABR (median PFS 26.6 months, 95% CI 15.1–38.1; p=0.345). One surgical patient (3%) had an acute ILD exacerbation <30 days post-surgery. No ILD exacerbations occurred after SABR <30 days. In total, ILD exacerbations occurred in 12.1% (n=4) of the surgery group and 14.2% (n=5) of the SABR group (median time 4.3 vs. 3.8 months, p=0.531). Postoperative complications grade =2 occurred in 7 patients (21%), with grade 4 in 2 (6%) and grade 5 in 1 (3%). Radiation pneumonitis grade =2 was observed in 20% (n=7), with grade 5 in 2 SABR patients (6%) and a median onset of 2.5 months (95% CI 2.4-2.7).Conclusion:
In this real-world cohort, median OS following SABR was 26.6 months, aligning with ASPIRE-ILD outcomes (25 months). ILD exacerbation and radiation pneumonitis rates were similar. SABR outcomes in a less fit population were comparable to surgery, underscoring the feasibility of both approaches. Potential risks should not preclude treatment in this population.