Both stereotactic ablative radiotherapy (SABR) and surgery can offer potentially curative treatment for selected patients with early-stage lung cancer and coexisting interstitial lung disease (ILD), despite concerns about treatment-related toxicity, according to real-world data from a specialist multidisciplinary programme.

Managing early-stage lung cancer in patients with ILD remains challenging because both surgery and radiotherapy carry a risk of pulmonary complications in a population already burdened by impaired lung function and reduced life expectancy.

However, evidence to guide treatment selection has been limited, with previous prospective studies involving relatively small numbers of patients.

To address this evidence gap, research from the Amsterdam University Medical Centre, published in the journal Radiotherapy and Oncology, evaluated outcomes among patients with stage 1 or 2 lung cancer and coexisting ILD treated through a dedicated multidisciplinary ILD-lung cancer programme.

The retrospective study included 67 patients who underwent curative-intent treatment between 2006 and 2024. Of these, 33 patients had surgical resection and 34 received SABR.

Surgical patients were generally younger and had better performance status than those treated with SABR.

The primary endpoints were progression-free survival (PFS) and overall survival (OS). Secondary outcomes included local, locoregional and distant disease control, treatment-related toxicity and prognostic factors.

Survival outcomes with SABR and surgery

After a median follow-up of 40 months, two-year PFS was 54% following surgery and 53% following SABR. Two-year OS was 68% and 56%, respectively. Although unadjusted analyses suggested a numerical survival advantage with surgery, these differences were not statistically significant.

Following inverse probability treatment weighting to account for baseline differences between groups, no significant differences were observed for either PFS or OS.

SABR also achieved high rates of local tumour control, with one-, two- and three-year rates of 92%, 88% and 80%, respectively. Corresponding local control rates following surgery were 86% at one year, with no further local progression observed thereafter.

Notably, SABR produced comparable outcomes despite being used in an older, less fit patient population, supporting its role as a feasible curative alternative when surgery may be less suitable.

Progressive pulmonary fibrosis a key prognostic factor

Overall, 16 pulmonary adverse events occurred in 14 patients (21%), including three ILD exacerbations, six postoperative complications and seven cases of radiation pneumonitis. There were no significant differences in pulmonary toxicity between the SABR and surgery treatment groups.

However, poorer performance status, idiopathic pulmonary fibrosis (IPF) and lower forced vital capacity were associated with an increased risk of pulmonary adverse events.

The analysis also identified progressive pulmonary fibrosis as an important prognostic factor. In multivariable analyses, this remained independently associated with worse OS and PFS, irrespective of treatment modality.

According to the authors, this finding underscores the importance of characterising the ILD subtype when assessing prognosis and planning treatment.

Study limitations included the retrospective design, relatively small sample size and the potential for residual confounding despite statistical adjustment. Selection bias was also possible because only patients considered suitable for curative treatment were included, the authors said. In addition, some toxicity events may have been under-recognised during follow-up.

Despite these limitations, the authors concluded that both surgery and SABR represent appropriate curative treatment options for selected patients with stage one or two lung cancer and coexisting ILD. They emphasised the value of multidisciplinary assessment involving ILD and thoracic oncology specialists to balance treatment benefits against potential risks.

Future research should now investigate whether advances such as motion-managed SABR and minimally invasive surgical techniques can further reduce treatment-related morbidity without compromising oncological outcomes, the authors concluded.

Reference
Tomassen ML et al. Outcomes of stereotactic ablative radiotherapy or surgery for early-stage lung cancer in patients with interstitial lung disease. Radiother Oncol 2026;220:111588.