ENO2 and cryptogenic organizing pneumonia: Pooled results showed that serum NSE in the early phase was associated with a higher risk of DNS in adult patients of acute COP during follow-up (OR for per 1 ng/mL increment of NSE: 1.10, 95% CI: 1.06–1.15, P < 0.001; Figure 2) with moderate heterogeneity (I2 ═ 46%).