Glasgow prognostic score for prediction of chemotherapy‐triggered acute exacerbation interstitial lung disease in patients with small cell lung cancer

BACKGROUND: Predicting the incidence of chemotherapy‐triggered acute exacerbation of interstitial lung disease (AE‐ILD) in patients with lung cancer is important because AE‐ILD confers a poor prognosis. The Glasgow prognostic score (GPS), which is an inflammation‐based index composed of serum levels of C‐reactive protein and albumin, predicts prognosis in patients with small cell lung cancer (SCLC) without ILD. In this study, we investigated AE‐ILD and survival outcome based on the GPS in patients with ILD associated with SCLC who were receiving chemotherapy. METHODS: Medical records of patients who received platinum‐based first‐line chemotherapy between June 2010 and May 2019 were retrospectively reviewed to compare the incidence of AE‐ILD and overall survival (OS) between GPS 0, 1, and 2. RESULTS: Among our cohort of 31 patients, six (19.3%) experienced chemotherapy‐triggered AE‐ILD. The AE‐ILD incidence increased from 9.5% to 25.0% and 50.0% with increase in GPS of 0, 1, and 2, respectively. Univariate and multivariate analyses revealed remarkable associations between GPS 2 and both AE‐ILD (odds ratio for GPS 2, 18.69; p = 0.046) and prognosis (hazard ratio of GPS 2, 13.52; p = 0.002). Furthermore, median OS in the GPS 0, 1, and 2 groups was 16.2, 9.8, and 7.1 months, respectively (p < 0.001). CONCLUSIONS: Our results suggest that GPS 2 is both a predictor of risk of chemotherapy‐triggered AE‐ILD and a prognostic indicator in patients with ILD associated with SCLC. We propose that GPS may be used as a guide to distinguish chemotherapy‐tolerant patients from those at high risk of AE‐ILD.