<abstract xmlns="http://www.w3.org/1999/xhtml">

<sec><h3>Background</h3>
<p>The relationship between interstitial lung abnormalities (ILAs) and the outcomes of lung cancer radiotherapy is unclear. This study investigated whether specific ILA subtypes are risk factors for radiation pneumonitis (RP).</p>
</sec>
<sec><h3>Patients and methods</h3>
<p>This retrospective study analysed patients with non-small cell lung cancer treated with radical-intent or salvage radiotherapy. Patients were categorised into normal (no abnormalities), ILA, and interstitial lung disease (ILD) groups. The ILA group was further subclassified into non-subpleural (NS), subpleural non-fibrotic (SNF), and subpleural fibrotic (SF) types. The Kaplan–Meier and Cox regression methods were used to determine RP and survival rates and compare these outcomes between groups, respectively.</p>
</sec>
<sec><h3>Results</h3>
<p>Overall, 175 patients (normal, n = 105; ILA-NS, n = 5; ILA-SNF, n = 28; ILA-SF, n = 31; ILD, n = 6) were enrolled. Grade ≥2 RP was observed in 71 (41%) patients. ILAs (hazard ratio [HR]: 2.33, p = 0.008), intensity-modulated radiotherapy (HR: 0.38, p = 0.03), and lung volume receiving 20 Gy (HR: 54.8, p = 0.03) contributed to the cumulative incidence of RP. Eight patients with grade 5 RP were in the ILA group, seven of whom had ILA-SF. Among radically treated patients, the ILA group had worse 2-year overall survival (OS) than the normal group (35.3% vs 54.6%, p = 0.005). Multivariate analysis revealed that the ILA-SF group contributed to poor OS (HR: 3.07, p =0.02).</p>
</sec>
<sec><h3>Conclusions</h3>
<p>ILAs, particularly ILA-SF, may be important risk factors for RP, which can worsen prognosis. These findings may aid in making decisions regarding radiotherapy.</p>
</sec>
</abstract>

Background
The relationship between interstitial lung abnormalities (ILAs) and the outcomes of lung cancer radiotherapy is unclear. This study investigated whether specific ILA subtypes are risk factors for radiation pneumonitis (RP).

Patients and methods
This retrospective study analysed patients with non-small cell lung cancer treated with radical-intent or salvage radiotherapy. Patients were categorised into normal (no abnormalities), ILA, and interstitial lung disease (ILD) groups. The ILA group was further subclassified into non-subpleural (NS), subpleural non-fibrotic (SNF), and subpleural fibrotic (SF) types. The Kaplan–Meier and Cox regression methods were used to determine RP and survival rates and compare these outcomes between groups, respectively.

Results
Overall, 175 patients (normal, n = 105; ILA-NS, n = 5; ILA-SNF, n = 28; ILA-SF, n = 31; ILD, n = 6) were enrolled. Grade ≥2 RP was observed in 71 (41%) patients. ILAs (hazard ratio [HR]: 2.33, p = 0.008), intensity-modulated radiotherapy (HR: 0.38, p = 0.03), and lung volume receiving 20 Gy (HR: 54.8, p = 0.03) contributed to the cumulative incidence of RP. Eight patients with grade 5 RP were in the ILA group, seven of whom had ILA-SF. Among radically treated patients, the ILA group had worse 2-year overall survival (OS) than the normal group (35.3% vs 54.6%, p = 0.005). Multivariate analysis revealed that the ILA-SF group contributed to poor OS (HR: 3.07, p =0.02).

Conclusions
ILAs, particularly ILA-SF, may be important risk factors for RP, which can worsen prognosis. These findings may aid in making decisions regarding radiotherapy.

Subpleural fibrotic interstitial lung abnormalities are implicated in non-small cell lung cancer radiotherapy outcomes

Department of Respiratory Medicine and Allergology

Department of Biostatistics, Clinical Research Center

Division of Chest Surgery, Department of Surgery

Radiology and Oncology

This work is licensed under the Creative Commons Attribution 4.0 International License.

Background
The relationship between interstitial lung abnormalities (ILAs) and the outcomes of lung cancer radiotherapy is unclear. This study investigated...

Subpleural fibrotic interstitial lung abnormalities are implicated in non-small cell lung cancer radiotherapy outcomes

Article Category: Research Article

Publicado en línea: 20 abr 2023

Páginas: 229 - 238

Recibido: 19 feb 2023

Aceptado: 02 abr 2023

DOI: https://doi.org/10.2478/raon-2023-0018

Palabras clave
interstitial lung abnormality, subpleural fibrosis, non-small cell lung cancer, radiotherapy, radiation pneumonitis, survival analysis

© 2023 Makoto Ito et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Subpleural fibrotic interstitial lung abnormalities are implicated in non-small cell lung cancer radiotherapy outcomes

Article Category: Research Article

Publicado en línea: 20 abr 2023

Páginas: 229 - 238

Recibido: 19 feb 2023

Aceptado: 02 abr 2023

DOI: https://doi.org/10.2478/raon-2023-0018

Palabras claveinterstitial lung abnormality, subpleural fibrosis, non-small cell lung cancer, radiotherapy, radiation pneumonitis, survival analysis

© 2023 Makoto Ito et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Palabras clave
interstitial lung abnormality, subpleural fibrosis, non-small cell lung cancer, radiotherapy, radiation pneumonitis, survival analysis