Protective effect of bevacizumab on chemotherapy-related acute exacerbation of interstitial lung disease in patients with advanced non-squamous non-small cell lung cancer

Background: Acute exacerbation of interstitial lung disease (AE-ILD) is the most serious complication in lung cancer patients with pre-existing ILD receiving chemotherapy. The role of vascular endothelial growth factor (VEGF) in pathogenesis of AE-ILD is conflicting. The influence of bevacizumab (Bev), a monoclonal antibody against VEGF, on lung cancer patients with pre-existing ILD remains unclear. We examined the effect of Bev on reducing AE-ILD risk in non-squamous non-small cell lung cancer (NSCLC) patients receiving chemotherapy. Methods: We analysed incidence of AE-ILD and outcomes of 48 patients with advanced non-squamous NSCLC with ILD who received first-line chemotherapy with (Bev group, n = 17) and without (non-Bev group, n = 31) Bev between July 2011 and July 2016. Gray's test, which was competing risk analysis during the study period, was performed for both groups. Results: The most common regimen used for first-line chemotherapy was the combination of carboplatin plus pemetrexed (PEM) in both groups. The incidences of chemotherapy-related AE-ILD 120 days after first-line chemotherapy initiation were significantly lower in the Bev than in the non-Bev groups (0% vs. 22.6%, p = 0.037, Gray's test). However, there were no differences in development of progressive disease of lung cancer and other events as the competing risk factors of AE-ILD between the two groups. Only patients receiving PEM-containing regimens also showed a significant difference in the incidence of AE-ILD between the two groups (p = 0.044). The overall-cumulative incidence of AE-ILD during the first-line and subsequent chemotherapy was 29.2% (14 of the 48). The median progression-free survival was significantly longer in the Bev than in the non-Bev groups (8.0 vs. 4.3 months, p = 0.026). Conclusions: The addition of Bev to chemotherapy regimens may reduce the risk of chemotherapy-related AE-ILD in patients with lung cancer.