In addition, increased CEA, NSE, and CYFRA21-1 in serum were significantly more common in the RP-ILD group than in the C-ILD group with incidence rates of 31.6 vs. 11.5%, 51.2 vs. 36.6%, and 66.7 vs. 38.2%, respectively. The gene discussed is ENO2; the disease is interstitial lung disease.